Primary Ciliary Dyskinesia 47 and Lissencephaly

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Classifications

Harrison's Part

Mechanistic Nosology

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Inheritance

1

Autosomal recessive HP:0000007

All reported affected individuals carry homozygous (autosomal-recessive) loss-of-function variants in TP73, identified in consanguineous and unrelated families by whole-exome sequencing.

Autosomal recessive inheritance

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"we identified homozygous loss-of-function variants in TP73 in seven individuals from five unrelated families"

Establishes autosomal-recessive inheritance with homozygous TP73 loss-of-function variants across five unrelated families.

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Mechanistic Hypotheses

2

Cajal-Retzius / Reelin Migration Model

reelin_cajal_retzius EMERGING

Evidence balance 1 support

TP73 (p73) is coexpressed with reelin in Cajal-Retzius neurons of the developing cortex and hippocampus. Under this model, loss of TP73 depletes or dysregulates Reelin-producing Cajal-Retzius cells, impairing the Reelin-dependent radial-migration signal that guides cortical lamination and thereby producing the lissencephaly.

Pathograph links

Defective Cortical Neuronal Migration -> Lissencephaly Disrupted radial neuronal migration produces a smooth-cortex malformation (mechanism unresolved; see mechanistic_hypotheses).

Show evidence (1 reference)

PMID:15054064 SUPPORT In Vitro

"In the fetal human hippocampus, Cajal-Retzius (CR) cells coexpress p73, a p53-family member involved in cell survival and apoptosis, and the glycoprotein reelin, crucial for radial migration."

Establishes the p73-Reelin coupling in human Cajal-Retzius cells that underlies this migration model.

Unifying Cilia/Cytoskeletal Program Model

cilia_migration_unifying EMERGING

Evidence balance 1 support

An alternative, non-exclusive model holds that the single TAp73-driven multiciliogenesis/cytoskeletal transcriptional program that builds airway and ependymal motile cilia also underlies neuronal migration, so its loss provides one unifying mechanism for the airway, ependymal (hydrocephalus), and cortical (lissencephaly, hippocampal dysgenesis) phenotypes seen in p73-null mice and in affected individuals. The two models are not mutually exclusive.

Pathograph links

Defective Cortical Neuronal Migration -> Lissencephaly Disrupted radial neuronal migration produces a smooth-cortex malformation (mechanism unresolved; see mechanistic_hypotheses).

Show evidence (1 reference)

PMID:26947080 SUPPORT Model Organism

"Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes observed in p73 knockout mice including hydrocephalus; hippocampal dysgenesis; sterility; and chronic inflammation/infection of lung, middle ear, and sinus."

Frames a single loss-of-ciliary-program mechanism unifying the CNS and airway phenotypes of p73 loss.

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Discussions and Knowledge Gaps

1

Does the p73-null mouse ependymal/hydrocephalus phenotype faithfully model the human cortical malformation, given that overt hydrocephalus is largely absent in the reported human cohort (only transient prenatal ventriculomegaly in one individual)?

HUMAN MODEL MISMATCH OPEN cild47-mouse-hydrocephalus-mismatch

Attached to

pathophysiology#Defective Cortical Neuronal Migration

The unifying cilia/cytoskeletal hypothesis for the human lissencephaly rests substantially on the p73-null mouse CNS phenotype, which is dominated by hydrocephalus. Because overt hydrocephalus is largely absent in humans, the translational validity of the mouse ependymal phenotype to the human cortical malformation is an open question.

Show evidence (1 reference)

PMID:26947080 SUPPORT Model Organism

"Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes observed in p73 knockout mice including hydrocephalus; hippocampal dysgenesis; sterility; and chronic inflammation/infection of lung, middle ear, and sinus."

Documents the prominent hydrocephalus of the p73-null mouse, the model phenotype whose human correlate is largely absent.

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Pathophysiology

5

TP73 Loss of Function

Biallelic loss-of-function variants abolish the transcriptional activity of TP73 (particularly the transactivation-domain-containing TAp73 isoforms). TP73 belongs to the TP53 family of transcription factors; its non-oncogenic role as the master regulator of multiciliogenesis was first revealed in knockout mice.

DNA-binding transcription factor activity GO:0003700 ↓ DECREASED

Downstream

Impaired Multiciliated Cell Differentiation Loss of TP73 transcriptional activity blocks the multiciliogenesis program.

Defective Cortical Neuronal Migration Loss of TP73 in Cajal-Retzius neurons disrupts Reelin-dependent radial migration during corticogenesis.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"TP73 belongs to the TP53 family of transcription factors and has therefore been well studied in cancer research. Studies in mice, however, have revealed non-oncogenic activities related to multiciliogenesis."

Identifies TP73 as a TP53-family transcription factor with a multiciliogenesis role, the activity abolished by loss-of-function variants.

Impaired Multiciliated Cell Differentiation

TAp73 acts upstream of the ciliogenic transcription factors FOXJ1 and RFX2 to drive differentiation of multiciliated cells. In TP73-deficient respiratory epithelium the number of MCCs is severely reduced, mirrored by a reduced number of cells expressing FOXJ1 and RFX2. In mouse models, TAp73 regulates ~50 genes required for ciliary formation and motility and its target FOXJ1 rescues the ciliary defect when re-expressed.

multiciliated epithelial cell CL:0005012

multi-ciliated epithelial cell differentiation GO:1903251 ↓ DECREASED

Downstream

Motile Cilia Deficiency and Basal Body Mislocalization Failure of MCC differentiation yields fewer, shorter, mislocalized motile cilia.

Show evidence (3 references)

PMID:34077761 SUPPORT Human Clinical

"The number of MCCs is severely reduced, consistent with a reduced number of cells expressing the transcription factors crucial for multiciliogenesis (FOXJ1, RFX2)."

Directly demonstrates that TP73 loss reduces multiciliated cell differentiation via loss of FOXJ1/RFX2-expressing cells.

PMID:27257214 SUPPORT Model Organism

"identify TAp73 as the conserved central transcriptional integrator of multiciliogenesis"

Establishes TAp73 as the central transcription factor controlling airway multiciliogenesis, the program lost in CILD47.

PMID:26947080 SUPPORT Model Organism

"We report that p73 is expressed in multiciliated cells (MCCs), is required for MCC differentiation, and directly regulates transcriptional modulators of multiciliogenesis."

Demonstrates in murine cells that p73 (TP73) is required for multiciliated cell differentiation and directly regulates the FOXJ1-associated multiciliogenesis gene network.

Motile Cilia Deficiency and Basal Body Mislocalization

TP73-deficient respiratory epithelial cells display reduced ciliary length and basal bodies that are mislocalized within the cytoplasm rather than docked at the apical membrane, together with a severely reduced number of multiciliated cells. This is a motile-cilia-arm ciliopathy mechanism, but distinct from classic PCD: the defect is a failure to generate normal numbers of motile cilia (a differentiation/docking defect) rather than an axonemal dynein-arm defect in an otherwise assembled cilium.

multiciliated columnar cell of tracheobronchial tree CL:0002145

cilium movement GO:0003341 ⚠ ABNORMAL cilium assembly GO:0060271 ⚠ ABNORMAL

Downstream

Impaired Mucociliary Clearance Deficient and dysfunctional motile cilia cannot clear airway mucus.

Abnormal ciliary motility Reduced ciliary length and number is observed clinically as abnormal ciliary function on high-speed video microscopy.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"The respiratory epithelial cells studied display reduced ciliary length and basal bodies mislocalized within the cytoplasm."

Documents the cellular ciliary phenotype: shortened cilia and mislocalized basal bodies in patient respiratory epithelium.

Impaired Mucociliary Clearance

The reduced number and length of motile cilia on airway epithelium impairs mucociliary clearance, the coordinated ciliary transport of mucus and trapped particles out of the respiratory tract. The resulting mucus stasis drives chronic and recurrent upper and lower airway infection.

multiciliated columnar cell of tracheobronchial tree CL:0002145

mucociliary clearance GO:0120197 ↓ DECREASED

lung UBERON:0002048

Downstream

Chronic airway disease Mucus stasis drives chronic and recurrent airway infection.

Bronchiectasis Sustained infection and airway damage lead to bronchiectasis.

Otitis media Impaired clearance in the middle ear causes recurrent otitis media.

Neonatal respiratory distress Early-onset airway disease presents as neonatal respiratory distress in a subset.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"All affected individuals exhibit a chronic airway disease as well as a brain malformation consistent with lissencephaly."

Links the ciliary defect to the clinical mucociliary clearance disorder (chronic airway disease) in all affected individuals.

Defective Cortical Neuronal Migration

Beyond the airway, TP73 is expressed in Cajal-Retzius neurons of the developing cortex, where it is coexpressed with reelin, the glycoprotein that is crucial for radial neuronal migration and cortical lamination. The mechanism linking TP73 loss to lissencephaly is not established; two non-exclusive hypotheses are proposed. (1) A Cajal-Retzius/Reelin arm: loss of TP73 in Reelin-coexpressing Cajal-Retzius neurons disrupts Reelin-dependent radial migration. (2) A unifying cilia/cytoskeletal arm: the same TAp73-driven multiciliogenesis/cytoskeletal program that builds airway and ependymal motile cilia also underlies neuronal migration, so its loss provides a single mechanism for the airway, ependymal, and cortical phenotypes of p73-null mice (which show hydrocephalus and hippocampal dysgenesis). Either route disrupts radial neuronal migration, producing the cortical malformation (lissencephaly / agyria-pachygyria, anterior-predominant, often with a corpus callosum abnormality) seen in affected individuals.

Cajal-Retzius / Reelin Migration Model Unifying Cilia/Cytoskeletal Program Model

Cajal-Retzius cell CL:0000695 radial glial cell CL:0000681

neuron migration GO:0001764 ⚠ ABNORMAL cerebral cortex radially oriented cell migration GO:0021799 ⚠ ABNORMAL

Downstream

Lissencephaly Disrupted radial neuronal migration produces a smooth-cortex malformation (mechanism unresolved; see mechanistic_hypotheses).

Global developmental delay The diffuse cortical malformation causes global developmental delay and intellectual disability.

Intellectual disability The cortical malformation results in intellectual disability.

Pachygyria Anterior-predominant pachygyria is part of the cortical malformation spectrum.

Abnormal corpus callosum morphology Corpus callosum hypoplasia/agenesis accompanies the migration defect.

Axial hypotonia Cortical malformation is associated with central (axial) hypotonia.

Show evidence (2 references)

PMID:15054064 SUPPORT In Vitro

"In the fetal human hippocampus, Cajal-Retzius (CR) cells coexpress p73, a p53-family member involved in cell survival and apoptosis, and the glycoprotein reelin, crucial for radial migration."

Couples TP73 (p73) to the Reelin radial-migration pathway in human Cajal-Retzius cells (human fetal-tissue immunohistochemistry), the basis of the Reelin hypothesis for the lissencephaly.

PMID:26947080 SUPPORT Model Organism

"Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes observed in p73 knockout mice including hydrocephalus; hippocampal dysgenesis; sterility; and chronic inflammation/infection of lung, middle ear, and sinus."

Supports the unifying cilia/cytoskeletal hypothesis, in which loss of the p73-driven ciliary program accounts for the CNS (hydrocephalus, hippocampal dysgenesis) as well as airway phenotypes of p73-null mice.

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Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.

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Phenotypes

12

Ear 1

Otitis media HP:0000388

Reported in the Wallmeier et al. 2021 full text; not quotable from the indexed abstract, so no evidence item is attached.

Immune 1

Chronic airway disease VERY_FREQUENT Recurrent respiratory infections HP:0002205

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"All affected individuals exhibit a chronic airway disease as well as a brain malformation consistent with lissencephaly."

Chronic airway disease from the mucociliary clearance defect was present in all affected individuals.

Nervous System 4

Global developmental delay HP:0001263

Inferred from the universal lissencephaly; per-patient neurodevelopmental detail is in the Wallmeier et al. 2021 full text and is not quotable from the indexed abstract, so no evidence item is attached here pending a quotable source.

Intellectual disability HP:0001249

Per-patient cognitive detail is in the Wallmeier et al. 2021 full text and is not quotable from the indexed abstract; no evidence item is attached pending a quotable source.

Abnormal corpus callosum morphology Hypoplasia of the corpus callosum HP:0002079

Reported in the Wallmeier et al. 2021 full text as part of the neuroimaging phenotype; not quotable from the indexed abstract, so no evidence item is attached.

Ventriculomegaly HP:0002119

Reported in the Wallmeier et al. 2021 full text; not quotable from the indexed abstract, so no evidence item is attached. See the HUMAN_MODEL_MISMATCH discussion on the mouse-vs-human hydrocephalus discrepancy. Intentionally left without an inbound pathograph edge: ventriculomegaly here is an ependymal / CSF-flow phenotype, not a product of the cortical neuronal-migration node, so wiring it to Defective Cortical Neuronal Migration would mis-model it.

Respiratory 2

Bronchiectasis HP:0002110

Documented in the primary Wallmeier et al. 2021 case series (full text); no snippet-verifiable statement is present in the indexed PubMed abstract, so no evidence item is attached here pending a quotable source.

Neonatal respiratory distress HP:0002643

Reported in a subset (approximately 4/7) in the Wallmeier et al. 2021 full text; not quotable from the indexed abstract, so no evidence item is attached.

Other 4

Lissencephaly VERY_FREQUENT HP:0001339

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"All affected individuals exhibit a chronic airway disease as well as a brain malformation consistent with lissencephaly."

All affected individuals had a brain malformation consistent with lissencephaly.

Abnormal ciliary motility Ciliary dyskinesia HP:0012265

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"The respiratory epithelial cells studied display reduced ciliary length and basal bodies mislocalized within the cytoplasm."

Documents abnormal ciliary structure/function (short cilia, mislocalized basal bodies) in patient cells.

Pachygyria HP:0001302

Anterior-predominant pachygyria is the radiological description in the Wallmeier et al. 2021 full text; it refines the abstract's "malformation consistent with lissencephaly" and is not separately quotable from the abstract, so no evidence item is attached.

Axial hypotonia HP:0008936

Reported in the Wallmeier et al. 2021 full text; not quotable from the indexed abstract, so no evidence item is attached.

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Genetic Associations

1

TP73

Gene: TP73 hgnc:12003 relationship_type: CAUSATIVE

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"Our data demonstrate that autosomal-recessive deleterious variants in the TP53 family member TP73 cause a mucociliary clearance disorder due to a defect in MCC differentiation."

Identifies TP73 as the causal gene and defines the mechanism as a defect in multiciliated cell differentiation.

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Medical Actions

3

Airway Clearance and Respiratory Infection Management

Action: Supportive Care NCIT:C15747

As for other forms of primary ciliary dyskinesia, management is supportive and directed at the mucociliary clearance defect: airway clearance physiotherapy, prompt and often prophylactic antibiotics for recurrent respiratory infections, and surveillance for bronchiectasis. There is no disease-modifying therapy that restores multiciliated cell differentiation.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"autosomal-recessive deleterious variants in the TP53 family member TP73 cause a mucociliary clearance disorder due to a defect in MCC differentiation"

The disorder is a mucociliary clearance disorder, the target of supportive airway-clearance management analogous to other primary ciliary dyskinesias.

Genetic Counseling

Action: Genetic Counseling NCIT:C15240

Genetic counseling for an autosomal-recessive condition, with recurrence-risk discussion and carrier/cascade testing, is indicated — especially given the consanguinity common in reported families.

Neurodevelopmental Rehabilitation and Physical Therapy

Action: Physical Therapy NCIT:C15302

Supportive management of the neurodevelopmental phenotype (physical, occupational, and speech therapy) addresses hypotonia and developmental delay.

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Diagnosis

2

Genetic Testing (Whole-Exome Sequencing / TP73)

Whole-exome sequencing, or a PCD/ciliopathy gene panel including TP73, is the definitive diagnostic approach. The combination of PCD-like airway disease with lissencephaly should specifically prompt TP73 testing.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"Utilizing whole-exome sequencing analysis in a cohort of individuals with a mucociliary clearance disorder and cortical malformation, we identified homozygous loss-of-function variants in TP73"

Whole-exome sequencing on the combined airway + cortical-malformation phenotype was the diagnostic route to the TP73 variants.

Ciliary Cell-Biology Workup (immunofluorescence, HSVM, TEM)

The airway phenotype is characterized with high-speed video microscopy, immunofluorescence, and transmission electron microscopy of respiratory epithelial cells to assess ciliary function, ciliary length, and the number of multiciliated cells (MCCs). CRITICAL PITFALL: unlike classic axonemal PCD, the axonemal ultrastructure on TEM is essentially normal in CILD47, so standard TEM-based PCD screening is falsely reassuring; the diagnostic signal is a reduced number and length of MCCs by immunofluorescence, not an axonemal defect.

The normal-axonemal-ultrastructure ("normal TEM") pitfall is detailed in the Wallmeier et al. 2021 full text; it is the key point distinguishing this RGMC disorder from axonemal PCD and is summarized here rather than snippet-quoted from the abstract.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"We performed high-speed video microscopy, immunofluorescence analyses, and transmission electron microscopy in respiratory epithelial cells after spheroid or air liquid interface culture to analyze ciliary function, ciliary length, and number of multiciliated cells (MCCs)."

Defines the cellular diagnostic workup used to characterize the ciliary phenotype.

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Prevalence

1

Worldwide

Cases In Literature Ultra Rare

Ultra-rare; first described in 2021 in seven individuals from five unrelated families. No population prevalence estimate is available.

Show evidence (1 reference)

PMID:34077761 SUPPORT Human Clinical

"we identified homozygous loss-of-function variants in TP73 in seven individuals from five unrelated families"

The disease is known from a single small case series, consistent with ultra-rare occurrence.

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Animal Models

1

Trp73-null (p73-/-) and TAp73 isoform-specific knockout Mouse Engineered knockout

p73-null (Trp73-/-) mice are the dominant mechanistic model for this entry. They show reduced and shortened airway motile cilia with chronic respiratory infection, plus CNS phenotypes (hydrocephalus, hippocampal dysgenesis) and sterility; TAp73 isoform-specific knockouts phenocopy the airway defect, establishing TAp73 as the multiciliogenesis regulator whose loss underlies the human disease. The mouse shows prominent hydrocephalus that is largely absent in the human cohort (see the HUMAN_MODEL_MISMATCH discussion).

Species

Mouse

Genotype

Trp73-null (p73-/-) and TAp73 isoform-specific knockout

Genes

TP73 hgnc:12003

Show evidence (2 references)

PMID:26947080 SUPPORT Model Organism

"Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes observed in p73 knockout mice including hydrocephalus; hippocampal dysgenesis; sterility; and chronic inflammation/infection of lung, middle ear, and sinus."

Documents the p73-null mouse multi-organ phenotype attributed to loss of the ciliary program.

PMID:27257214 SUPPORT Model Organism

"identify TAp73 as the conserved central transcriptional integrator of multiciliogenesis"

TAp73 isoform-specific analysis in mouse airway cells establishes TAp73 as the central multiciliogenesis regulator.

{ }

Source YAML

click to show

name: Primary Ciliary Dyskinesia 47 and Lissencephaly
creation_date: "2026-07-31T20:30:00Z"
category: Genetic
disease_term:
  preferred_term: ciliary dyskinesia, primary, 47, and lissencephaly
  term:
    id: MONDO:0030346
    label: ciliary dyskinesia, primary, 47, and lissencephaly
description: >-
  Primary ciliary dyskinesia 47 with lissencephaly (CILD47, OMIM 619466) is a
  rare autosomal-recessive motile ciliopathy caused by biallelic loss-of-function
  variants in TP73. Unlike classic primary ciliary dyskinesia, which arises from
  structural axonemal defects that leave an assembled cilium unable to beat, CILD47
  belongs to the "reduced generation of multiple motile cilia" (RGMC) subgroup
  (alongside MCIDAS-, CCNO-, and FOXJ1-related disease): TP73, a member of the TP53
  transcription-factor family, is the master transcriptional regulator of
  multiciliated cell (MCC) differentiation, acting upstream of FOXJ1 and RFX
  factors. Loss of TP73 severely reduces the number of MCCs and produces fewer,
  shorter motile cilia with basal bodies mislocalized in the cytoplasm, impairing
  mucociliary clearance and causing chronic airway disease. On mechanistic
  grounds, laterality defects (situs inversus) would not be expected in an RGMC
  disorder, because embryonic nodal monocilia are not products of the
  multiciliated-cell differentiation program that TP73 governs — a conceptual
  contrast with classic axonemal PCD, where the same axonemal machinery drives
  both airway cilia and nodal monocilia. TP73 is also expressed in Cajal-Retzius neurons where it is coupled
  to the Reelin pathway that guides radial neuronal migration; its loss produces a
  cortical malformation consistent with lissencephaly. The combination of a
  mucociliary clearance disorder with lissencephaly distinguishes CILD47 from other
  forms of primary ciliary dyskinesia.
parents:
- Primary Ciliary Dyskinesia
- Ciliopathy
inheritance:
- name: Autosomal recessive
  description: >-
    All reported affected individuals carry homozygous (autosomal-recessive)
    loss-of-function variants in TP73, identified in consanguineous and unrelated
    families by whole-exome sequencing.
  inheritance_term:
    preferred_term: Autosomal recessive inheritance
    term:
      id: HP:0000007
      label: Autosomal recessive inheritance
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      we identified homozygous loss-of-function variants in TP73 in seven
      individuals from five unrelated families
    explanation: >-
      Establishes autosomal-recessive inheritance with homozygous TP73
      loss-of-function variants across five unrelated families.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
genetic:
- name: TP73
  gene_term:
    preferred_term: TP73
    term:
      id: hgnc:12003
      label: TP73
  relationship_type: CAUSATIVE
  notes: >-
    Biallelic loss-of-function variants in TP73 (tumor protein p73), a member of
    the TP53 transcription-factor family, are the cause of CILD47. TP73 is the
    master transcriptional regulator of multiciliated cell differentiation and is
    also required for normal corticogenesis. Variant spectrum (Wallmeier et al.
    2021, full text): all reported alleles are null / loss-of-function and were
    homozygous — a multi-exon deletion, a canonical splice-donor variant, and
    frameshift and nonsense variants across the five families; all disrupt both the
    TAp73 and the DeltaNp73 isoform classes. Penetrance is complete in reported
    homozygotes, consanguinity is the dominant ascertainment factor, and no genetic
    modifiers have been established. Exact cDNA/protein coordinates live in the
    primary full text and are not quotable from the indexed abstract, so they are
    summarized here at the variant-class level rather than asserted as
    snippet-verified evidence.
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Our data demonstrate that autosomal-recessive deleterious variants in the
      TP53 family member TP73 cause a mucociliary clearance disorder due to a
      defect in MCC differentiation.
    explanation: >-
      Identifies TP73 as the causal gene and defines the mechanism as a defect
      in multiciliated cell differentiation.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
pathophysiology:
- name: TP73 Loss of Function
  biological_scale: MOLECULAR
  description: >-
    Biallelic loss-of-function variants abolish the transcriptional activity of
    TP73 (particularly the transactivation-domain-containing TAp73 isoforms). TP73
    belongs to the TP53 family of transcription factors; its non-oncogenic role as
    the master regulator of multiciliogenesis was first revealed in knockout mice.
  molecular_functions:
  - preferred_term: DNA-binding transcription factor activity
    term:
      id: GO:0003700
      label: DNA-binding transcription factor activity
    modifier: DECREASED
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      TP73 belongs to the TP53 family of transcription factors and has therefore
      been well studied in cancer research. Studies in mice, however, have
      revealed non-oncogenic activities related to multiciliogenesis.
    explanation: >-
      Identifies TP73 as a TP53-family transcription factor with a
      multiciliogenesis role, the activity abolished by loss-of-function variants.
    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
  downstream:
  - target: Impaired Multiciliated Cell Differentiation
    description: Loss of TP73 transcriptional activity blocks the multiciliogenesis program.
  - target: Defective Cortical Neuronal Migration
    description: >-
      Loss of TP73 in Cajal-Retzius neurons disrupts Reelin-dependent radial
      migration during corticogenesis.

- name: Impaired Multiciliated Cell Differentiation
  biological_scale: CELLULAR
  description: >-
    TAp73 acts upstream of the ciliogenic transcription factors FOXJ1 and RFX2 to
    drive differentiation of multiciliated cells. In TP73-deficient respiratory
    epithelium the number of MCCs is severely reduced, mirrored by a reduced number
    of cells expressing FOXJ1 and RFX2. In mouse models, TAp73 regulates ~50 genes
    required for ciliary formation and motility and its target FOXJ1 rescues the
    ciliary defect when re-expressed.
  cell_types:
  - preferred_term: multiciliated epithelial cell
    term:
      id: CL:0005012
      label: multiciliated epithelial cell
  biological_processes:
  - preferred_term: multi-ciliated epithelial cell differentiation
    term:
      id: GO:1903251
      label: multi-ciliated epithelial cell differentiation
    modifier: DECREASED
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The number of MCCs is severely reduced, consistent with a reduced number of
      cells expressing the transcription factors crucial for multiciliogenesis
      (FOXJ1, RFX2).
    explanation: >-
      Directly demonstrates that TP73 loss reduces multiciliated cell
      differentiation via loss of FOXJ1/RFX2-expressing cells.
    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
  - reference: PMID:27257214
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      identify TAp73 as the conserved central transcriptional integrator of
      multiciliogenesis
    explanation: >-
      Establishes TAp73 as the central transcription factor controlling airway
      multiciliogenesis, the program lost in CILD47.
    reference_title: TAp73 is a central transcriptional regulator of airway multiciliogenesis.
  - reference: PMID:26947080
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      We report that p73 is expressed in multiciliated cells (MCCs), is required
      for MCC differentiation, and directly regulates transcriptional modulators
      of multiciliogenesis.
    explanation: >-
      Demonstrates in murine cells that p73 (TP73) is required for multiciliated
      cell differentiation and directly regulates the FOXJ1-associated
      multiciliogenesis gene network.
    reference_title: p73 Is Required for Multiciliogenesis and Regulates the Foxj1-Associated Gene Network.
  downstream:
  - target: Motile Cilia Deficiency and Basal Body Mislocalization
    description: Failure of MCC differentiation yields fewer, shorter, mislocalized motile cilia.

- name: Motile Cilia Deficiency and Basal Body Mislocalization
  biological_scale: CELLULAR
  conforms_to: "ciliopathy_dysfunction#Motile Cilia Beat Dysfunction"
  description: >-
    TP73-deficient respiratory epithelial cells display reduced ciliary length and
    basal bodies that are mislocalized within the cytoplasm rather than docked at
    the apical membrane, together with a severely reduced number of multiciliated
    cells. This is a motile-cilia-arm ciliopathy mechanism, but distinct from
    classic PCD: the defect is a failure to generate normal numbers of motile cilia
    (a differentiation/docking defect) rather than an axonemal dynein-arm defect in
    an otherwise assembled cilium.
  cell_types:
  - preferred_term: multiciliated columnar cell of tracheobronchial tree
    term:
      id: CL:0002145
      label: multiciliated columnar cell of tracheobronchial tree
  biological_processes:
  - preferred_term: cilium movement
    term:
      id: GO:0003341
      label: cilium movement
    modifier: ABNORMAL
  - preferred_term: cilium assembly
    term:
      id: GO:0060271
      label: cilium assembly
    modifier: ABNORMAL
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The respiratory epithelial cells studied display reduced ciliary length and
      basal bodies mislocalized within the cytoplasm.
    explanation: >-
      Documents the cellular ciliary phenotype: shortened cilia and mislocalized
      basal bodies in patient respiratory epithelium.
    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
  downstream:
  - target: Impaired Mucociliary Clearance
    description: Deficient and dysfunctional motile cilia cannot clear airway mucus.
  - target: Abnormal ciliary motility
    description: >-
      Reduced ciliary length and number is observed clinically as abnormal ciliary
      function on high-speed video microscopy.

- name: Impaired Mucociliary Clearance
  biological_scale: TISSUE
  description: >-
    The reduced number and length of motile cilia on airway epithelium impairs
    mucociliary clearance, the coordinated ciliary transport of mucus and trapped
    particles out of the respiratory tract. The resulting mucus stasis drives
    chronic and recurrent upper and lower airway infection.
  cell_types:
  - preferred_term: multiciliated columnar cell of tracheobronchial tree
    term:
      id: CL:0002145
      label: multiciliated columnar cell of tracheobronchial tree
  locations:
  - preferred_term: lung
    term:
      id: UBERON:0002048
      label: lung
  biological_processes:
  - preferred_term: mucociliary clearance
    term:
      id: GO:0120197
      label: mucociliary clearance
    modifier: DECREASED
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      All affected individuals exhibit a chronic airway disease as well as a brain
      malformation consistent with lissencephaly.
    explanation: >-
      Links the ciliary defect to the clinical mucociliary clearance disorder
      (chronic airway disease) in all affected individuals.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
  downstream:
  - target: Chronic airway disease
    description: Mucus stasis drives chronic and recurrent airway infection.
  - target: Bronchiectasis
    description: Sustained infection and airway damage lead to bronchiectasis.
  - target: Otitis media
    description: Impaired clearance in the middle ear causes recurrent otitis media.
  - target: Neonatal respiratory distress
    description: Early-onset airway disease presents as neonatal respiratory distress in a subset.
- name: Defective Cortical Neuronal Migration
  biological_scale: TISSUE
  description: >-
    Beyond the airway, TP73 is expressed in Cajal-Retzius neurons of the developing
    cortex, where it is coexpressed with reelin, the glycoprotein that is crucial
    for radial neuronal migration and cortical lamination. The mechanism linking
    TP73 loss to lissencephaly is not established; two non-exclusive hypotheses are
    proposed. (1) A Cajal-Retzius/Reelin arm: loss of TP73 in Reelin-coexpressing
    Cajal-Retzius neurons disrupts Reelin-dependent radial migration. (2) A unifying
    cilia/cytoskeletal arm: the same TAp73-driven multiciliogenesis/cytoskeletal
    program that builds airway and ependymal motile cilia also underlies neuronal
    migration, so its loss provides a single mechanism for the airway, ependymal,
    and cortical phenotypes of p73-null mice (which show hydrocephalus and
    hippocampal dysgenesis). Either route disrupts radial neuronal migration,
    producing the cortical malformation (lissencephaly / agyria-pachygyria,
    anterior-predominant, often with a corpus callosum abnormality) seen in
    affected individuals.
  cell_types:
  - preferred_term: Cajal-Retzius cell
    term:
      id: CL:0000695
      label: Cajal-Retzius cell
  - preferred_term: radial glial cell
    term:
      id: CL:0000681
      label: radial glial cell
  biological_processes:
  - preferred_term: neuron migration
    term:
      id: GO:0001764
      label: neuron migration
    modifier: ABNORMAL
  - preferred_term: cerebral cortex radially oriented cell migration
    term:
      id: GO:0021799
      label: cerebral cortex radially oriented cell migration
    modifier: ABNORMAL
  evidence:
  - reference: PMID:15054064
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      In the fetal human hippocampus, Cajal-Retzius (CR) cells coexpress p73, a
      p53-family member involved in cell survival and apoptosis, and the
      glycoprotein reelin, crucial for radial migration.
    explanation: >-
      Couples TP73 (p73) to the Reelin radial-migration pathway in human
      Cajal-Retzius cells (human fetal-tissue immunohistochemistry), the basis of
      the Reelin hypothesis for the lissencephaly.
    reference_title: p73 and Reelin in Cajal-Retzius cells of the developing human hippocampal formation.
  - reference: PMID:26947080
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes
      observed in p73 knockout mice including hydrocephalus; hippocampal
      dysgenesis; sterility; and chronic inflammation/infection of lung, middle
      ear, and sinus.
    explanation: >-
      Supports the unifying cilia/cytoskeletal hypothesis, in which loss of the
      p73-driven ciliary program accounts for the CNS (hydrocephalus, hippocampal
      dysgenesis) as well as airway phenotypes of p73-null mice.
    reference_title: p73 Is Required for Multiciliogenesis and Regulates the Foxj1-Associated Gene Network.
  downstream:
  - target: Lissencephaly
    description: >-
      Disrupted radial neuronal migration produces a smooth-cortex malformation
      (mechanism unresolved; see mechanistic_hypotheses).
    hypothesis_groups:
    - reelin_cajal_retzius
    - cilia_migration_unifying
  - target: Global developmental delay
    description: >-
      The diffuse cortical malformation causes global developmental delay and
      intellectual disability.
  - target: Intellectual disability
    description: The cortical malformation results in intellectual disability.
  - target: Pachygyria
    description: Anterior-predominant pachygyria is part of the cortical malformation spectrum.
  - target: Abnormal corpus callosum morphology
    description: Corpus callosum hypoplasia/agenesis accompanies the migration defect.
  - target: Axial hypotonia
    description: Cortical malformation is associated with central (axial) hypotonia.

phenotypes:
- name: Lissencephaly
  category: Neurological
  description: >-
    Cortical brain malformation with an abnormally smooth cortical surface
    (reduced or absent gyri), reflecting a neuronal migration defect. Present in
    all reported affected individuals.
  phenotype_term:
    preferred_term: Lissencephaly
    term:
      id: HP:0001339
      label: Lissencephaly
  frequency: VERY_FREQUENT
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      All affected individuals exhibit a chronic airway disease as well as a brain
      malformation consistent with lissencephaly.
    explanation: All affected individuals had a brain malformation consistent with lissencephaly.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
- name: Chronic airway disease
  category: Respiratory
  description: >-
    Chronic and recurrent respiratory disease resulting from impaired mucociliary
    clearance, present in all reported affected individuals.
  phenotype_term:
    preferred_term: Recurrent respiratory infections
    term:
      id: HP:0002205
      label: Recurrent respiratory infections
  frequency: VERY_FREQUENT
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      All affected individuals exhibit a chronic airway disease as well as a brain
      malformation consistent with lissencephaly.
    explanation: Chronic airway disease from the mucociliary clearance defect was present in all affected individuals.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
- name: Abnormal ciliary motility
  category: Cellular
  description: >-
    High-speed video microscopy and cell-culture analyses of patient respiratory
    epithelium show abnormal ciliary function with reduced ciliary length and a
    severely reduced number of multiciliated cells.
  phenotype_term:
    preferred_term: Ciliary dyskinesia
    term:
      id: HP:0012265
      label: Ciliary dyskinesia
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The respiratory epithelial cells studied display reduced ciliary length and
      basal bodies mislocalized within the cytoplasm.
    explanation: >-
      Documents abnormal ciliary structure/function (short cilia, mislocalized
      basal bodies) in patient cells.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
- name: Bronchiectasis
  category: Respiratory
  description: >-
    Bronchiectasis is the recognized structural airway sequela of the chronic
    mucociliary-clearance failure and recurrent lower-respiratory infection in
    CILD47, as in other primary ciliary dyskinesias.
  phenotype_term:
    preferred_term: Bronchiectasis
    term:
      id: HP:0002110
      label: Bronchiectasis
  notes: >-
    Documented in the primary Wallmeier et al. 2021 case series (full text); no
    snippet-verifiable statement is present in the indexed PubMed abstract, so no
    evidence item is attached here pending a quotable source.
- name: Global developmental delay
  category: Neurological
  description: >-
    Developmental delay / intellectual disability is an expected consequence of
    the diffuse cortical malformation (lissencephaly) in affected individuals.
  phenotype_term:
    preferred_term: Global developmental delay
    term:
      id: HP:0001263
      label: Global developmental delay
  notes: >-
    Inferred from the universal lissencephaly; per-patient neurodevelopmental
    detail is in the Wallmeier et al. 2021 full text and is not quotable from the
    indexed abstract, so no evidence item is attached here pending a quotable source.
- name: Intellectual disability
  category: Neurological
  description: >-
    Moderate-to-severe intellectual disability accompanies the cortical
    malformation in affected individuals.
  phenotype_term:
    preferred_term: Intellectual disability
    term:
      id: HP:0001249
      label: Intellectual disability
  notes: >-
    Per-patient cognitive detail is in the Wallmeier et al. 2021 full text and is
    not quotable from the indexed abstract; no evidence item is attached pending a
    quotable source.
- name: Pachygyria
  category: Neurological
  description: >-
    The cortical malformation is described as anterior-predominant
    pachygyria/lissencephaly (a spectrum with the lissencephaly phenotype).
  phenotype_term:
    preferred_term: Anterior-predominant pachygyria
    term:
      id: HP:0001302
      label: Pachygyria
  notes: >-
    Anterior-predominant pachygyria is the radiological description in the
    Wallmeier et al. 2021 full text; it refines the abstract's "malformation
    consistent with lissencephaly" and is not separately quotable from the
    abstract, so no evidence item is attached.
- name: Abnormal corpus callosum morphology
  category: Neurological
  description: >-
    A corpus callosum abnormality (hypoplasia to agenesis, variable across
    patients) is a defining MRI feature accompanying the cortical malformation.
  phenotype_term:
    preferred_term: Hypoplasia of the corpus callosum
    term:
      id: HP:0002079
      label: Hypoplasia of the corpus callosum
  notes: >-
    Reported in the Wallmeier et al. 2021 full text as part of the neuroimaging
    phenotype; not quotable from the indexed abstract, so no evidence item is
    attached.
- name: Axial hypotonia
  category: Neurological
  description: Central (axial) hypotonia is reported in affected individuals.
  phenotype_term:
    preferred_term: Axial hypotonia
    term:
      id: HP:0008936
      label: Axial hypotonia
  notes: >-
    Reported in the Wallmeier et al. 2021 full text; not quotable from the indexed
    abstract, so no evidence item is attached.
- name: Otitis media
  category: Otolaryngological
  description: >-
    Recurrent otitis media results from impaired mucociliary clearance in the
    middle ear, as in other primary ciliary dyskinesias.
  phenotype_term:
    preferred_term: Otitis media
    term:
      id: HP:0000388
      label: Otitis media
  notes: >-
    Reported in the Wallmeier et al. 2021 full text; not quotable from the indexed
    abstract, so no evidence item is attached.
- name: Neonatal respiratory distress
  category: Respiratory
  description: >-
    Neonatal respiratory distress (some requiring ventilatory support) reflects
    early-onset airway disease in a subset of affected individuals.
  phenotype_term:
    preferred_term: Neonatal respiratory distress
    term:
      id: HP:0002643
      label: Neonatal respiratory distress
  notes: >-
    Reported in a subset (approximately 4/7) in the Wallmeier et al. 2021 full
    text; not quotable from the indexed abstract, so no evidence item is attached.
- name: Ventriculomegaly
  category: Neurological
  description: >-
    Prenatal ventriculomegaly was reported in one individual (transient, resolved
    postnatally); overt hydrocephalus was largely absent in the human cohort,
    contrasting with the p73-null mouse.
  phenotype_term:
    preferred_term: Ventriculomegaly
    term:
      id: HP:0002119
      label: Ventriculomegaly
  notes: >-
    Reported in the Wallmeier et al. 2021 full text; not quotable from the indexed
    abstract, so no evidence item is attached. See the HUMAN_MODEL_MISMATCH
    discussion on the mouse-vs-human hydrocephalus discrepancy. Intentionally left
    without an inbound pathograph edge: ventriculomegaly here is an ependymal /
    CSF-flow phenotype, not a product of the cortical neuronal-migration node, so
    wiring it to Defective Cortical Neuronal Migration would mis-model it.
treatments:
- name: Airway Clearance and Respiratory Infection Management
  description: >-
    As for other forms of primary ciliary dyskinesia, management is supportive and
    directed at the mucociliary clearance defect: airway clearance physiotherapy,
    prompt and often prophylactic antibiotics for recurrent respiratory infections,
    and surveillance for bronchiectasis. There is no disease-modifying therapy that
    restores multiciliated cell differentiation.
  treatment_term:
    preferred_term: Supportive Care
    term:
      id: NCIT:C15747
      label: Supportive Care
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      autosomal-recessive deleterious variants in the TP53 family member TP73
      cause a mucociliary clearance disorder due to a defect in MCC differentiation
    explanation: >-
      The disorder is a mucociliary clearance disorder, the target of supportive
      airway-clearance management analogous to other primary ciliary dyskinesias.

    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
- name: Genetic Counseling
  description: >-
    Genetic counseling for an autosomal-recessive condition, with recurrence-risk
    discussion and carrier/cascade testing, is indicated — especially given the
    consanguinity common in reported families.
  treatment_term:
    preferred_term: Genetic Counseling
    term:
      id: NCIT:C15240
      label: Genetic Counseling
- name: Neurodevelopmental Rehabilitation and Physical Therapy
  description: >-
    Supportive management of the neurodevelopmental phenotype (physical,
    occupational, and speech therapy) addresses hypotonia and developmental delay.
  therapeutic_modality: BEHAVIORAL
  treatment_term:
    preferred_term: Physical Therapy
    term:
      id: NCIT:C15302
      label: Physical Therapy
mechanistic_hypotheses:
- hypothesis_group_id: reelin_cajal_retzius
  hypothesis_label: Cajal-Retzius / Reelin Migration Model
  status: EMERGING
  description: >-
    TP73 (p73) is coexpressed with reelin in Cajal-Retzius neurons of the
    developing cortex and hippocampus. Under this model, loss of TP73 depletes or
    dysregulates Reelin-producing Cajal-Retzius cells, impairing the
    Reelin-dependent radial-migration signal that guides cortical lamination and
    thereby producing the lissencephaly.
  evidence:
  - reference: PMID:15054064
    reference_title: p73 and Reelin in Cajal-Retzius cells of the developing human hippocampal formation.
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      In the fetal human hippocampus, Cajal-Retzius (CR) cells coexpress p73, a
      p53-family member involved in cell survival and apoptosis, and the
      glycoprotein reelin, crucial for radial migration.
    explanation: >-
      Establishes the p73-Reelin coupling in human Cajal-Retzius cells that
      underlies this migration model.
- hypothesis_group_id: cilia_migration_unifying
  hypothesis_label: Unifying Cilia/Cytoskeletal Program Model
  status: EMERGING
  description: >-
    An alternative, non-exclusive model holds that the single TAp73-driven
    multiciliogenesis/cytoskeletal transcriptional program that builds airway and
    ependymal motile cilia also underlies neuronal migration, so its loss provides
    one unifying mechanism for the airway, ependymal (hydrocephalus), and cortical
    (lissencephaly, hippocampal dysgenesis) phenotypes seen in p73-null mice and
    in affected individuals. The two models are not mutually exclusive.
  evidence:
  - reference: PMID:26947080
    reference_title: p73 Is Required for Multiciliogenesis and Regulates the Foxj1-Associated Gene Network.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes
      observed in p73 knockout mice including hydrocephalus; hippocampal
      dysgenesis; sterility; and chronic inflammation/infection of lung, middle
      ear, and sinus.
    explanation: >-
      Frames a single loss-of-ciliary-program mechanism unifying the CNS and
      airway phenotypes of p73 loss.

diagnosis:
- name: Genetic Testing (Whole-Exome Sequencing / TP73)
  description: >-
    Whole-exome sequencing, or a PCD/ciliopathy gene panel including TP73, is the
    definitive diagnostic approach. The combination of PCD-like airway disease with
    lissencephaly should specifically prompt TP73 testing.
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      Utilizing whole-exome sequencing analysis in a cohort of individuals with a
      mucociliary clearance disorder and cortical malformation, we identified
      homozygous loss-of-function variants in TP73
    explanation: >-
      Whole-exome sequencing on the combined airway + cortical-malformation
      phenotype was the diagnostic route to the TP73 variants.
    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
- name: Ciliary Cell-Biology Workup (immunofluorescence, HSVM, TEM)
  description: >-
    The airway phenotype is characterized with high-speed video microscopy,
    immunofluorescence, and transmission electron microscopy of respiratory
    epithelial cells to assess ciliary function, ciliary length, and the number of
    multiciliated cells (MCCs). CRITICAL PITFALL: unlike classic axonemal PCD, the
    axonemal ultrastructure on TEM is essentially normal in CILD47, so standard
    TEM-based PCD screening is falsely reassuring; the diagnostic signal is a
    reduced number and length of MCCs by immunofluorescence, not an axonemal defect.
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We performed high-speed video microscopy, immunofluorescence analyses, and
      transmission electron microscopy in respiratory epithelial cells after
      spheroid or air liquid interface culture to analyze ciliary function, ciliary
      length, and number of multiciliated cells (MCCs).
    explanation: Defines the cellular diagnostic workup used to characterize the ciliary phenotype.
    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.
  notes: >-
    The normal-axonemal-ultrastructure ("normal TEM") pitfall is detailed in the
    Wallmeier et al. 2021 full text; it is the key point distinguishing this RGMC
    disorder from axonemal PCD and is summarized here rather than snippet-quoted
    from the abstract.

prevalence:
- population: Worldwide
  measure_type: CASES_IN_LITERATURE
  prevalence_class: ULTRA_RARE
  notes: >-
    Ultra-rare; first described in 2021 in seven individuals from five unrelated
    families. No population prevalence estimate is available.
  evidence:
  - reference: PMID:34077761
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      we identified homozygous loss-of-function variants in TP73 in seven
      individuals from five unrelated families
    explanation: >-
      The disease is known from a single small case series, consistent with
      ultra-rare occurrence.
    reference_title: Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.

animal_models:
- species: Mouse
  genotype: Trp73-null (p73-/-) and TAp73 isoform-specific knockout
  category: Engineered knockout
  description: >-
    p73-null (Trp73-/-) mice are the dominant mechanistic model for this entry.
    They show reduced and shortened airway motile cilia with chronic respiratory
    infection, plus CNS phenotypes (hydrocephalus, hippocampal dysgenesis) and
    sterility; TAp73 isoform-specific knockouts phenocopy the airway defect,
    establishing TAp73 as the multiciliogenesis regulator whose loss underlies the
    human disease. The mouse shows prominent hydrocephalus that is largely absent
    in the human cohort (see the HUMAN_MODEL_MISMATCH discussion).
  genes:
  - preferred_term: TP73
    term:
      id: hgnc:12003
      label: TP73
  evidence:
  - reference: PMID:26947080
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes
      observed in p73 knockout mice including hydrocephalus; hippocampal
      dysgenesis; sterility; and chronic inflammation/infection of lung, middle
      ear, and sinus.
    explanation: >-
      Documents the p73-null mouse multi-organ phenotype attributed to loss of the
      ciliary program.
    reference_title: p73 Is Required for Multiciliogenesis and Regulates the Foxj1-Associated Gene Network.
  - reference: PMID:27257214
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      identify TAp73 as the conserved central transcriptional integrator of
      multiciliogenesis
    explanation: >-
      TAp73 isoform-specific analysis in mouse airway cells establishes TAp73 as
      the central multiciliogenesis regulator.
    reference_title: TAp73 is a central transcriptional regulator of airway multiciliogenesis.

discussions:
- discussion_id: cild47-mouse-hydrocephalus-mismatch
  kind: HUMAN_MODEL_MISMATCH
  status: OPEN
  attaches_to:
  - pathophysiology#Defective Cortical Neuronal Migration
  prompt: >-
    Does the p73-null mouse ependymal/hydrocephalus phenotype faithfully model the
    human cortical malformation, given that overt hydrocephalus is largely absent
    in the reported human cohort (only transient prenatal ventriculomegaly in one
    individual)?
  rationale: >-
    The unifying cilia/cytoskeletal hypothesis for the human lissencephaly rests
    substantially on the p73-null mouse CNS phenotype, which is dominated by
    hydrocephalus. Because overt hydrocephalus is largely absent in humans, the
    translational validity of the mouse ependymal phenotype to the human cortical
    malformation is an open question.
  evidence:
  - reference: PMID:26947080
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Loss of ciliary biogenesis provides a unifying mechanism for many phenotypes
      observed in p73 knockout mice including hydrocephalus; hippocampal
      dysgenesis; sterility; and chronic inflammation/infection of lung, middle
      ear, and sinus.
    explanation: >-
      Documents the prominent hydrocephalus of the p73-null mouse, the model
      phenotype whose human correlate is largely absent.
    reference_title: p73 Is Required for Multiciliogenesis and Regulates the Foxj1-Associated Gene Network.

classifications:
  harrisons_chapter:
  - classification_value: RESPIRATORY
  - classification_value: NEUROLOGIC
  - classification_value: GENETICS_ENVIRONMENT_DISEASE
  mechanistic_category:
  - classification_value: ciliopathy

references:
- reference: PMID:34077761
  title: "Mutations in TP73 cause impaired mucociliary clearance and lissencephaly."

📚

References & Deep Research

References

1

PMID:34077761

Mutations in TP73 cause impaired mucociliary clearance and lissencephaly.

No top-level findings curated for this source.

Deep Research

1

Claude Code ▸

1. Disease Information

claude-haiku-4-5-20251001, claude-sonnet-5 2026-07-31T22:14:31.477298

1. Disease Information

Overview: Primary Ciliary Dyskinesia-47 and Lissencephaly (CILD47) is an ultra-rare autosomal recessive disorder caused by biallelic loss-of-function variants in TP73 (the p53-family transcription factor gene). It combines a motile-ciliopathy respiratory phenotype (chronic mucociliary clearance failure) with a neurodevelopmental phenotype (anterior-predominant lissencephaly/pachygyria with corpus callosum abnormality). Mechanistically it is not a classic axonemal-structure PCD but belongs to the "reduced generation of multiple motile cilia" (RGMC) subgroup — a defect in the transcriptional program that specifies multiciliated cell (MCC) differentiation itself, analogous to MCIDAS-, CCNO-, and FOXJ1-related disease, rather than a defect of the assembled axoneme (Wallmeier et al. 2021, PMID:34077761).

Key identifiers: - OMIM phenotype: #619466 — "Ciliary dyskinesia, primary, 47, and lissencephaly (CILD47)" - OMIM gene: 601990 — TP73 (tumor protein p73) - Gene location: 1p36.32 (HGNC:12003; NCBI Gene ID 7161) - MONDO/Orphanet: No independently verified MONDO or dedicated Orphanet ID was found in this search; the condition is recent (2021) and may only be indexed under a general PCD/RGMC or OMIM-derived term. This should be explicitly checked with OAK/MONDO lookup before curation rather than assumed. - Inheritance: Autosomal recessive - Distinguish from "isolated" lissencephaly (LIS1/PAFAH1B1, DCX, TUBA1A etc.) — TP73-lissencephaly is a syndromic, ciliopathy-associated* lissencephaly, mechanistically and radiologically distinct (see §6, §7).

Synonyms/alternative names: "TP73-related mucociliary clearance disorder and lissencephaly"; "CILD47"; occasionally described under the umbrella term "reduced generation of multiple motile cilia (RGMC) with lissencephaly."

Evidence basis: All currently published human data derive from a single case series — 7 affected individuals from 5 unrelated, mostly consanguineous families (Wallmeier et al. 2021, Am J Hum Genet 108(7):1318–1329, PMID:34077761) — supplemented by extensive mouse-model mechanistic literature on Trp73/TAp73 in ciliated epithelia (see §6, §15). This is aggregated disease-level case-series data, not large-cohort or EHR-derived data — sample size is a fundamental limitation for all epidemiological/prognostic claims below.

2. Etiology

Disease causal factor: Purely genetic — biallelic (homozygous or compound heterozygous) loss-of-function variants in TP73, disrupting both major isoform classes (TAp73, the N-terminally intact transactivating isoform, and ΔNp73, the N-terminally truncated isoform), resulting in complete TP73 protein deficiency (PMID:34077761).

Genetic risk factors: - Biallelic TP73 null alleles are causal and (based on the reported families) appear fully penetrant for the respiratory+CNS phenotype. - Consanguinity is a major risk factor observationally — "most families showed consanguinity" in the founding cohort (PMID:34077761), consistent with an autosomal recessive, presumably ultra-rare allele model with regional/familial enrichment rather than a common founder variant. - No modifier genes have yet been reported; genotype-phenotype correlation across the 5 families is not yet resolved (small n).

Environmental/lifestyle risk factors: None identified or plausible — this is a monogenic transcription-factor deficiency, not a multifactorial or exposure-modulated disease. No gene-environment interaction data exist.

Protective factors: None described. Heterozygous carriers (unaffected parents in all reported families) show no reported phenotype, consistent with recessive, non-haploinsufficient inheritance for this disease (distinct from TP73's proposed, unrelated, monoallelic-expression/tumor-suppressor role in neuroblastoma, which is a separate biological context — see §4).

3. Phenotypes

Respiratory phenotype (present in all 7 reported patients)

Phenotype	Type	Onset	Frequency (of 7)	Suggested HP term
Chronic recurrent respiratory tract infections	Sign/symptom	Neonatal–early childhood	7/7	HP:0002205 (Recurrent respiratory infections)
Neonatal respiratory distress requiring ventilation	Sign	Neonatal	4/7 (OP-1693 II1, OP-3039 II1, KI-645 II1, 20DG1336 II1)	HP:0002098 (Respiratory distress)
Productive cough	Symptom	Early childhood	Reported in all	HP:0031245 (Productive cough)
Chronic rhinitis	Sign	Early childhood	Reported in all	HP:0031417 (Chronic rhinitis) or HP:0012384
Otitis media (recurrent)	Sign	Early childhood	Reported in all	HP:0000388 (Otitis media)
Bronchiectasis, mucus plugging, atelectasis	Imaging finding	Progressive	Multiple patients	HP:0002110 (Bronchiectasis), HP:0002099 (Atelectasis)
Death from respiratory failure	Outcome	Infancy	1/7 (20DG1336 II1, died age 2 months)	—
Situs inversus	—	—	Absent in all patients (situs solitus)	— (important negative — distinguishes from classic axonemal PCD)

Neurological/CNS phenotype (present in all 7 reported patients)

Phenotype	Characteristics	Suggested HP term
Anterior-predominant ("frontoanterior") pachygyria/lissencephaly	Progressive/static malformation, present from birth (developmental)	HP:0007260 (Anterior pachygyria) or HP:0001339 (Lissencephaly)
Thin, hypoplastic, or absent corpus callosum	Variable severity across patients	HP:0002079 (Hypoplasia of the corpus callosum) / HP:0001274 (Agenesis of the corpus callosum)
Hippocampal dysplasia	Reported in ≥1 patient (OP-3039 II1)	HP:0007364 (Hippocampal malformation)
Central (axial) hypotonia	All patients	HP:0008936 (Central hypotonia)
Moderate-to-severe cognitive/intellectual impairment	Variable, all patients affected to some degree	HP:0002342 (Intellectual disability)
Seizure susceptibility	EEG abnormality noted in ≥1 patient (19DG0120)	HP:0001250 (Seizures)
Ventriculomegaly	Prenatal, resolved by age 3 in one patient (OP-1693 II1); overt hydrocephalus notably absent in the human cohort (contrasts with mouse model — see §6)	HP:0002119 (Ventriculomegaly)

Severity/progression: The lissencephaly and hypotonia/cognitive impairment are static developmental-malformation phenotypes; the respiratory disease is chronic and can progress to bronchiectasis and, in the most severe neonatal-onset cases, fatal respiratory failure. Frequency is based on n=7, so all frequency bands should be treated with caution (dismech convention: prefer qualitative framing over fabricated FREQUENT/OCCASIONAL percentages absent a larger cohort, per the project's frequency-evidence SOP).

Quality of life: No formal QoL instrument (EQ-5D, SF-36) data exist for this specific disease; impact is inferable as substantial (ventilator dependency in infancy, chronic lung disease, moderate–severe developmental impairment) but not separately quantified in the literature.

4. Genetic/Molecular Information

Causal gene: TP73 (HGNC:12003, NCBI Gene 7161, OMIM *601990), chromosome 1p36.32.

Reported pathogenic variants (all homozygous, all predicted loss-of-function, disrupting both TAp73 and ΔNp73 isoforms; from Wallmeier et al. 2021, PMID:34077761): 1. Homozygous deletion spanning exons 7–14 (~13.17 kb) — family OP-1693 2. c.1196+1G>A (canonical splice-donor variant, intron retention → premature stop) — families OP-3039 and KI-645 3. c.1459delT, p.Tyr487Thrfs11 (frameshift) — family 19DG0120 4. c.994C>T, p.Gln332 (nonsense) — families 18DG0963 and 19DG2776 (cousins) 5. c.613G>T, p.Glu205* (nonsense) — family 20DG1336

Variant classification: All variants would be classified pathogenic/likely pathogenic under ACMG/AMP criteria (null variant in a gene where LOF is an established disease mechanism, segregation in affected homozygotes, absence/rarity in population databases — gnomAD-level allele frequency data for these specific alleles were not retrieved in this search and should be checked directly against gnomAD before curation).

Functional consequence: Complete loss of TP73 protein function (both isoforms) → failure of the TAp73-driven multiciliogenesis transcriptional program (see §6).

Somatic vs. germline: Germline only — this is a constitutional Mendelian disorder, unrelated to TP73's somatic tumor-suppressor role in cancers (note: TP73/1p36 is also studied as a candidate tumor-suppressor locus in neuroblastoma and other cancers via a distinct, monoallelic-expression mechanism — that biology is not relevant to CILD47 and should not be conflated in curation).

Modifier genes: None established.

Epigenetics: No disease-specific DNA methylation/chromatin data for TP73-CILD47 were found. Note the general biology: TAp73 itself acts as a master transcriptional activator (not a chromatin modifier per se) of the multiciliogenesis network (FOXJ1, RFX2, RFX3, miR-34bc, and ~50 structural/functional ciliary genes) — see §6.

Chromosomal abnormalities: The exon 7–14 deletion in one family is effectively a small structural (contiguous-gene-region) deletion but confined to TP73 itself; no evidence of a broader 1p36 deletion syndrome phenotype overlap was reported.

HGNC/gene ontology suggestions: Gene: hgnc:12003 (TP73). Relevant GO molecular function: GO:0003700 (DNA-binding transcription factor activity); GO:0006355 (regulation of DNA-templated transcription).

5. Environmental Information

No environmental, occupational, toxin, dietary, lifestyle, or infectious-agent contributory factors have been described — this is a monogenic developmental/ciliopathy disorder. Recurrent respiratory infections are a consequence of impaired mucociliary clearance (secondary, not causal), typically involving common respiratory pathogens (e.g., Haemophilus influenzae, Pseudomonas aeruginosa, Staphylococcus aureus) as seen generally in PCD/chronic suppurative lung disease, though pathogen-specific data for this particular gene defect were not reported in the primary paper.

6. Mechanism / Pathophysiology

Causal chain (upstream → downstream):

Molecular trigger: Biallelic TP73 LOF → complete loss of TAp73 (and ΔNp73) protein.
Transcriptional failure: TAp73 normally acts as the central transcriptional regulator of the multiciliogenesis program, acting downstream of MCIDAS and upstream of FOXJ1, within the Notch1-dependent multiciliated-cell (MCC) differentiation pathway. TAp73 directly activates FOXJ1, RFX2, RFX3, miR-34b/c, and ~50 structural/functional ciliary genes (Nemajerova et al. 2016, Genes Dev 30(11):1300, PMID:27257214; a companion paper — Fernández-Alonso, Buscà, et al., PMID:27298333 — independently converged on the same conclusion; Marshall et al. 2016, Cell Rep 14(14):2289–300, PMID:26947080).
Cellular consequence — failure of MCC differentiation: In TP73-deficient human airway epithelial (ALI) cultures: severely reduced FOXJ1-positive and RFX2-positive nuclei; severely reduced numbers of ciliated cells (~20–30% apical MCC coverage vs. ~73% in controls, p<0.0001); markedly shortened residual cilia (~1.5–1.8 µm vs. ~3.8 µm in controls, p<0.0001); occasional basal-body mislocalization within the cytoplasm; and a broader epithelial differentiation defect (epithelial layer height 7–10 µm/2 cell layers vs. 39.9 µm/6 layers in controls) (PMID:34077761).
Functional consequence — impaired mucociliary transport: Particle-tracking assays showed severely reduced transport velocity and directionality, i.e., a physiologically defective mucociliary escalator — despite grossly normal axonemal ultrastructure by electron microscopy (9+2 microtubule arrangement intact; outer dynein arms/DNAH5 and nexin-dynein regulatory complex/GAS8 correctly localized) (PMID:34077761). This distinguishes CILD47 mechanistically from "classical" structural PCD (e.g., DNAH5, CCDC39/40 mutants) — the defect is in generating enough normal cilia, not in cilia that are structurally abnormal.
Clinical respiratory consequence: Chronic impaired mucociliary clearance → recurrent airway infection, bronchiectasis, and (in severe neonatal cases) respiratory failure.
Parallel CNS consequence: TP73/TAp73 also governs multiciliogenesis and planar cell polarity (PCP) of brain ependymal cells and is required for proper corticogenesis. Mouse Trp73-null models show ependymal ciliary and PCP defects, hydrocephalus, hippocampal dysgenesis, and cortical lamination/subventricular-zone (SVZ) architecture abnormalities (Fatt/Gonzalez-Cano et al. lineage of studies: "p73 is required for ependymal cell maturation and neurogenic SVZ cytoarchitecture"; Fuertes-Álvarez et al. 2018, Cell Death Dis 9(2):163, "p73 regulates ependymal planar cell polarity by modulating actin and microtubule cytoskeleton," PMID not independently confirmed in this pass — verify before citing; Fujitani et al. 2017, Sci Rep 7:12007, "Loss of p73 in ependymal cells during the perinatal period leads to aqueductal stenosis," PMID:28931858). In humans, this maps onto the observed cortical malformation (anterior pachygyria/lissencephaly with corpus callosum hypoplasia/agenesis) — the authors propose that loss of the same TAp73-driven multiciliogenesis/cytoskeletal program that builds airway MCCs also disrupts a cilia-related process needed for normal neuronal migration/cortical layering, unifying the dual-organ phenotype under one mechanism rather than two independent gene functions (PMID:34077761).

Cell types involved: - Airway multiciliated epithelial cells (MCCs) — CL:0002145 (ciliated columnar cell of tracheobronchial tree) or CL:1000271 (lung ciliated cell) - Brain ependymal cells (ciliated, line the ventricles) — CL:0000065 (ependymal cell) - Cortical neurons / radial glia (migration defect substrate) — CL:0000679 (glutamatergic neuron), CL:0002608 (radial glial cell)

Suggested GO biological process terms: - GO:0035082 (axoneme assembly) — indirectly, via reduced ciliogenesis - GO:0007368 (determination of left/right symmetry) — notably not disrupted (situs solitus preserved), useful negative annotation - GO:0060271 (cilium assembly) - GO:0021987 (cerebral cortex development) / GO:0021795 (cerebral cortex cell migration) - GO:0003356 (regulation of cilium beat frequency involved in ciliary motility) — downstream functional consequence

Subcellular: Basal body (GO:0005930 cilium; GO:0032391 photoreceptor connecting cilium is not relevant); centriole/basal body mislocalization is a described cell-biology finding, though core basal-body number was preserved (distinguishing from CCNO/MCIDAS-driven centriole-amplification failure — a related but mechanistically distinct RGMC subtype).

Omics: No transcriptomic (GEO/ArrayExpress), proteomic, or single-cell datasets specific to human TP73-CILD47 patient tissue were identified in this search; the mechanistic transcription-factor-network data (FOXJ1/RFX2/RFX3/miR-34bc target network) derive primarily from mouse/organoid TAp73 ChIP and knockout transcriptomic studies (PMID:27257214, PMID:26947080).

7. Anatomical Structures Affected

Organ level: - Primary: Respiratory tract (nasal/paranasal sinuses, middle ear, trachea, bronchi, lung parenchyma via airway disease) and central nervous system (cerebral cortex, corpus callosum, hippocampus). - Secondary/complication-level: Lower respiratory tract structural damage (bronchiectasis) as a consequence of chronic infection. - Body systems: Respiratory system and nervous system are the two systems with a documented human phenotype; reproductive system (efferent duct multiciliogenesis, sperm flagella) is affected in other MCIDAS/CCNO/GEMC1 RGMC-family diseases and in Trp73 mouse models (sterility), but human fertility data specific to TP73-CILD47 were not reported (patients are pediatric in the reported cohort).

Tissue/cell level: - Respiratory pseudostratified ciliated epithelium (multiciliated cells) — UBERON:0002185 (bronchial epithelium), UBERON:0001707 (nasal cavity epithelium) - Ependymal lining of brain ventricles — UBERON:0002316 (ependyma) - Cerebral cortex (neuronal migration substrate) — UBERON:0000956 (cerebral cortex); UBERON:0002336 (corpus callosum) - Hippocampus — UBERON:0002421

Subcellular: Cilium/axoneme (GO:0005929 cilium), basal body (GO:0005930).

Localization/laterality: Situs solitus preserved (no laterality defect) — an important distinguishing negative finding from classical axonemal PCD, where left-right patterning defects (situs inversus/heterotaxy) are common because nodal cilia require normal axonemal dynein function; here nodal cilia function is apparently unaffected, consistent with a selective MCC-differentiation (not axonemal-structural) defect.

8. Temporal Development

Onset: Congenital for the CNS malformation (developmental, present from birth/prenatally imageable); neonatal-to-early-childhood for respiratory disease onset — several patients presented with respiratory distress in the neonatal period requiring ventilatory support.
Onset pattern: The CNS malformation is a fixed structural defect (not "progressive" in the neurodegenerative sense) but its functional consequences (developmental delay, hypotonia, seizure risk) manifest and are characterized over infancy/childhood. Respiratory disease is chronic and can be insidious/progressive (recurrent infections → bronchiectasis) or acute/severe from birth.
Disease course: Chronic, lifelong for survivors (no described "remission"). One reported death (respiratory failure at 2 months) indicates a severe/fatal end of the phenotypic spectrum.
Critical periods: Neonatal period is the highest-risk window for respiratory decompensation; prenatal/perinatal window is when the cortical malformation is established (developmental, not preventable postnatally).
No formal staging system exists for this disease given its rarity.

9. Inheritance and Population

Epidemiology: No dedicated prevalence/incidence estimate exists for CILD47 specifically — only 7 individuals from 5 families have been published (PMID:34077761); it should be treated as ultra-rare/case-series-only. For context, PCD as a whole has classically cited prevalence of ~1 in 10,000–20,000, though a 2022 population-genomic (carrier-frequency-based) analysis of pathogenic variants across 29 PCD genes estimated a much higher global prevalence of ~13.2 per 100,000 (Zariwala/Zhu et al., "The global prevalence and ethnic heterogeneity of primary ciliary dyskinesia gene variants," PMID:35051411) — note TP73 was likely not among the "classical" 29 genes surveyed in earlier PCD gene panels given its 2021 discovery, so this estimate would not capture CILD47-specific carrier frequency.
Inheritance pattern: Autosomal recessive.
Penetrance: Appears complete/full in the reported homozygotes (all 7 affected).
Expressivity: Variable — severity of both the respiratory phenotype (ranging from chronic infections to fatal neonatal respiratory failure) and the CNS phenotype (variable corpus callosum hypoplasia vs. agenesis, variable cognitive impairment severity) across the 7 patients.
Consanguinity: A major contributing factor — most of the 5 founding families were consanguineous, consistent with a rare recessive allele being homozygosed via shared ancestry rather than a common population founder variant (contrast with, e.g., a single recurrent founder mutation).
Founder effects: Not established; the 5 families carry 5 different (largely private) LOF alleles, arguing against a single dominant founder variant, though the c.994C>T (p.Gln332*) variant recurred in two related (cousin) families (18DG0963/19DG2776), consistent with a family-specific founder allele rather than population-wide.
Carrier frequency: Not established for TP73 specifically.
Population demographics: The reported cohort includes patients ascertained via clinical/genetic centers with Middle Eastern (Saudi Arabian — e.g., patient IDs with "19DG"/"20DG" prefixes suggestive of Saudi genomic center nomenclature) and German/European referral patterns, consistent with the multinational, consanguinity-enriched ascertainment typical of ultra-rare AR ciliopathy case series; no formal geographic/ethnic prevalence data exist.
Sex ratio / age distribution: Not reported as skewed; cohort is pediatric (consistent with severe early-onset presentation).

10. Diagnostics

General PCD diagnostic framework (per ATS/ERS guidelines), adapted for this syndromic form: - Nasal nitric oxide (nNO): Standard PCD screening test; low nNO is typical in structural/axonemal PCD. Its behavior in TP73-CILD47 (an MCC-differentiation, not axonemal-structure, defect) was not explicitly reported in the retrieved data and should be checked directly against the primary paper before asserting a specific nNO value/finding. - High-speed video microscopy (ciliary beat pattern/frequency): Would be expected to show reduced/absent ciliary beating due to markedly reduced cilia number and length, though this is inferred from the cell-biology data (particle-tracking dysfunction) rather than a directly quoted clinical HSVA report. - Transmission electron microscopy (TEM): Reported as essentially normal axonemal ultrastructure (9+2 arrangement, normal outer dynein arms/DNAH5, normal nexin-dynein regulatory complex/GAS8) — an important diagnostic pitfall, since standard TEM-based PCD diagnosis could be falsely reassuring/normal in this gene defect; diagnosis instead rests on reduced MCC numbers and ciliary length (immunofluorescence for FOXJ1/acetylated tubulin) plus genetic testing. - Genetic testing: TP73 sequencing (single-gene or as part of an expanded PCD/ciliopathy gene panel) is the definitive diagnostic approach, especially when the combination of PCD-like respiratory disease plus lissencephaly is present — this combination should specifically trigger TP73 testing given the described disease. WES/WGS are appropriate given the syndromic (multi-organ) presentation and phenotypic novelty. - Brain MRI: Central to diagnosis of the neurological component — frontoanterior-predominant pachygyria/lissencephaly, thin/absent corpus callosum, ± hippocampal dysplasia. - Chest imaging (CT): Bronchiectasis, mucus plugging, atelectasis. - Situs assessment: Notably normal (situs solitus) — this is diagnostically useful as it can distinguish TP73-CILD47/RGMC-spectrum disease from classical PCD, where situs anomalies occur in ~50% of patients due to nodal cilia dysfunction.

Differential diagnosis: - Other RGMC-spectrum disorders: MCIDAS, CCNO, FOXJ1 (also cause reduced MCC numbers with normal axonemal ultrastructure and normal situs; FOXJ1 pathology can also involve hydrocephalus and, in some reports, laterality defects since FOXJ1 also functions in nodal cilia). - Classical structural PCD genes (DNAH5, DNAI1, CCDC39, CCDC40, etc.) — distinguished by abnormal TEM/axonemal structure and higher rate of situs anomalies. - Isolated (non-ciliopathy) lissencephaly syndromes (LIS1/PAFAH1B1, DCX, TUBA1A, ARX) — distinguished by absence of a respiratory/mucociliary phenotype. - Other syndromic ciliopathies with CNS + respiratory overlap (e.g., some CEP-gene ciliopathies) should be considered in the broader differential.

Screening: No population newborn-screening program exists for this ultra-rare condition; prenatal diagnosis/genetic counseling is feasible in known-carrier consanguineous families once a familial variant is identified.

11. Outcome/Prognosis

Mortality: 1 of 7 reported patients died of respiratory failure at 2 months of age — indicating a potentially high-severity subgroup with neonatal-onset, ventilator-dependent respiratory failure. No formal survival curve/life-expectancy estimate exists given the small cohort.
Morbidity: Chronic lung disease (bronchiectasis) is expected to be lifelong in survivors, analogous to other PCD forms. Neurodevelopmentally, all surviving patients have moderate-to-severe cognitive impairment and central hypotonia; some have seizure risk.
Recovery potential: The cortical malformation is a fixed structural defect with no expected anatomical recovery; developmental outcome depends on the degree of associated intellectual disability and access to supportive/rehabilitative therapy. Respiratory disease, as with other PCD, can be stabilized (not cured) with aggressive airway clearance and infection management, though data specific to long-term respiratory trajectory in TP73-CILD47 beyond the initial case series are not yet available.
Prognostic factors: Severity of the neonatal respiratory presentation (ventilator dependence) appears to correlate with the most severe outcomes (the one death occurred in a neonatal-ventilator-dependent patient); no molecular (variant-type) genotype-severity correlation has yet been established given the small, genetically heterogeneous cohort.

12. Treatment

No disease-specific (TP73-targeted) therapy exists. Management follows standard PCD supportive care, extrapolated from general PCD/RGMC management guidelines, plus standard neurodevelopmental/neurological supportive care for the CNS malformation:

Respiratory — supportive/standard-of-care: - Airway clearance therapy (chest physiotherapy, mechanical airway clearance devices) — NCIT:C15315 (Rehabilitation) / a specific airway-clearance NCIT term should be sourced. - Mucolytics / hypertonic saline nebulization — supportive care, NCIT:C15747 (Supportive Care). - Prophylactic/therapeutic antibiotics for recurrent respiratory infections (e.g., macrolides such as azithromycin, used in general PCD/bronchiectasis management for both antimicrobial and anti-inflammatory effect) — NCIT:C15986 (Pharmacotherapy) with therapeutic_agent bound to the specific antibiotic class as appropriate. - Ventilatory support in neonatal/severe presentations (NCIT — mechanical ventilation-type intervention term should be sourced specifically). - Otologic management for recurrent otitis media (e.g., tympanostomy tubes) — surgical/procedural, NCIT:C15329 (Surgical Procedure)-family term.

Neurological — supportive: - Physical, occupational, and speech therapy for hypotonia and developmental delay — NCIT:C15302 (Physical Therapy), NCIT:C121351 (Occupational Therapy), NCIT:C159273 (Speech Therapy). - Antiepileptic management if/when seizures manifest — standard pharmacotherapy, agent-specific. - Developmental/early intervention services.

Advanced/experimental therapeutics: None reported or in trials specific to TP73-CILD47 (no ClinicalTrials.gov entries identified in this search for this specific gene-disease pair). Gene therapy is not a near-term realistic option given the dual-organ (lung epithelium + CNS developmental) nature of the defect and the fact that the CNS malformation is a fixed prenatal/perinatal structural lesion rather than an ongoing degenerative process amenable to postnatal correction.

Treatment strategy: Multidisciplinary (pulmonology, neurology, developmental pediatrics, otolaryngology) supportive management; no published treatment algorithm specific to this gene-disease association exists — management should be extrapolated cautiously from general PCD and general lissencephaly/hypotonia care guidelines, explicitly noted as extrapolated rather than disease-specific evidence.

13. Prevention

Primary prevention: Not applicable in the traditional sense (monogenic developmental disorder) beyond genetic counseling for consanguineous/carrier families with a known familial TP73 variant, and prenatal diagnosis (chorionic villus sampling/amniocentesis with targeted variant testing, or prenatal ultrasound/fetal MRI surveillance for cortical malformation) in at-risk pregnancies once the familial variant is known — NCIT:C15240 (Genetic Counseling).
Secondary prevention: Early recognition of the combined respiratory + lissencephaly phenotype should prompt TP73 testing to enable earlier diagnosis, respiratory surveillance, and proactive infection management (reducing risk of the bronchiectasis/respiratory-failure trajectory).
Tertiary prevention: Aggressive airway clearance and infection control aimed at preventing progression to bronchiectasis and respiratory failure in diagnosed patients (extrapolated from general PCD management, not disease-specific evidence).
Screening: No population-level newborn screening exists; carrier screening is only practical within already-identified affected families/consanguineous populations.
Immunization: No disease-specific vaccine strategy, though standard respiratory-pathogen vaccination (influenza, pneumococcal, pertussis-containing) is a reasonable general recommendation by analogy to other chronic suppurative lung diseases, though not specifically documented for this condition.

14. Other Species / Natural Disease

No naturally occurring TP73-deficient disease has been reported in non-human species (no OMIA entries or veterinary case reports identified in this search). All non-human data derive from engineered mouse knockout models (see §15) rather than spontaneously occurring animal disease.

15. Model Organisms

Mouse (Mus musculus, NCBITaxon:10090) — Trp73 (mouse ortholog) knockout/conditional models — the primary and extensively characterized model system:

Trp73-null mice: Recapitulate multiple features of the human dual-organ phenotype, unifying several previously separately-described p73-knockout phenotypes under a single ciliogenesis-defect mechanism: chronic respiratory tract infections due to profound ciliogenesis defects and loss of mucociliary clearance, hydrocephalus, hippocampal dysgenesis, sterility, and chronic middle-ear/sinus inflammation (Nemajerova et al. 2016, Genes Dev, PMID:27257214; Marshall et al. 2016, Cell Rep, PMID:26947080).
TAp73 specifically (the N-terminal transactivating isoform) was shown to be necessary and sufficient for basal body docking, axonemal extension, and motility during MCC-progenitor differentiation in mouse organotypic airway (tracheal) cultures, and to directly bind and activate FOXJ1, RFX2, RFX3, and the miR-34bc locus (PMID:27257214).
Ependymal-specific conditional models: Perinatal loss of p73 in ependymal cells leads to aqueductal stenosis and disrupted ependymal planar cell polarity (actin/microtubule cytoskeleton), directly implicating the same TAp73-multiciliogenesis axis in the CNS ventricular-lining phenotype relevant to the human lissencephaly/ventricular findings (Fujitani et al. 2017, Sci Rep 7:12007, PMID:28931858; related work on p73/ependymal PCP and SVZ neurogenic cytoarchitecture from the same research lineage — cite with direct verification of exact PMIDs before KB entry).
Phenotype recapitulation vs. human disease: The mouse models recapitulate the airway MCC-differentiation defect and mucociliary clearance failure well, and support the mechanistic link between p73 loss and both ependymal/ciliary and cortical-architecture abnormalities. However, mouse Trp73-null models show more prominent hydrocephalus than the reported human cohort (where overt hydrocephalus was largely absent, aside from transient prenatal ventriculomegaly in one patient) — this is a candidate human-model mismatch worth flagging explicitly in any dismech curation (per the project's HUMAN_MODEL_MISMATCH discussion pattern) rather than assuming full concordance between the mouse hydrocephalus phenotype and the milder human ventricular findings.
In vitro human models: Patient-derived nasal/bronchial air-liquid-interface (ALI) epithelial cultures were the direct human cellular model used in Wallmeier et al. 2021 to demonstrate the MCC-differentiation and ciliary-transport defects described in §6 — this is IN_VITRO (human primary cell) evidence, distinct from the MODEL_ORGANISM (mouse) evidence above, and should be tagged accordingly in any evidence curation.

Resources: MGI (Mouse Genome Informatics) holds the Trp73 knockout allele records; no zebrafish, Drosophila, or C. elegans TP73-ortholog disease models specific to this phenotype were identified in this search.

Summary of Key Ontology Term Suggestions (to be independently OAK-verified before KB entry)

Category	Suggested term(s)
Disease	OMIM:619466; gene OMIM:601990; MONDO ID — unverified, must be looked up*
Gene	hgnc:12003 (TP73)
Phenotypes (HP)	Lissencephaly (HP:0001339), Anterior pachygyria, Hypoplasia/agenesis of corpus callosum (HP:0002079 / HP:0001274), Central hypotonia (HP:0008936), Intellectual disability (HP:0002342), Seizures (HP:0001250), Recurrent respiratory infections (HP:0002205), Bronchiectasis (HP:0002110), Otitis media (HP:0000388), Respiratory distress (HP:0002098)
Cell types (CL)	Ciliated columnar cell (CL:0002145 / CL:1000271), Ependymal cell (CL:0000065), Radial glial cell (CL:0002608)
Biological processes (GO)	Cilium assembly (GO:0060271), Axoneme assembly (GO:0035082), Cerebral cortex development (GO:0021987), Regulation of transcription (GO:0006355)
Anatomy (UBERON)	Bronchial epithelium (UBERON:0002185), Ependyma (UBERON:0002316), Cerebral cortex (UBERON:0000956), Corpus callosum (UBERON:0002336)
Treatment (NCIT)	Pharmacotherapy (NCIT:C15986), Physical Therapy (NCIT:C15302), Supportive Care (NCIT:C15747), Genetic Counseling (NCIT:C15240)

Key Primary Citations (PMIDs)

Wallmeier J, Bracht D, Alsaif HS, et al. Mutations in TP73 cause impaired mucociliary clearance and lissencephaly. Am J Hum Genet. 2021;108(7):1318–1329. PMID:34077761 — the founding/only human clinical-genetic case series (7 patients, 5 families).
Nemajerova A, Kramer D, Siller SS, et al. TAp73 is a central transcriptional regulator of airway multiciliogenesis. Genes Dev. 2016;30(11):1300–1312. PMID:27257214 — mouse mechanistic model.
Companion paper, "Unifying the p73 knockout phenotypes: TAp73 orchestrates multiciliogenesis," Genes Dev. 2016. PMID:27298333 — independent convergent mouse study (verify author list directly before citing).
Marshall CB, Mays DJ, Beeler JS, et al. p73 Is Required for Multiciliogenesis and Regulates the Foxj1-Associated Gene Network. Cell Rep. 2016;14(14):2289–2300. PMID:26947080.
Fujitani M, et al. Loss of p73 in ependymal cells during the perinatal period leads to aqueductal stenosis. Sci Rep. 2017;7:12007. PMID:28931858 — ependymal/CNS mouse mechanistic model.
General PCD context: Zariwala MA, Zhu X, et al., global prevalence/gene-variant analysis, PMID:35051411; ATS/ERS PCD diagnostic guidelines (multiple; verify exact current PMID before citing, as an updated version was found dated 2026 alongside the earlier 2017/2018 versions).

Important caveat for dismech curation: Several of the mechanistic mouse-model PMIDs above (notably the ependymal/PCP lineage of papers) were partially reconstructed from search-result summaries rather than fully verified against the primary abstract text in this pass. Per this project's own DR-verification SOP, every PMID and snippet listed here must be independently re-verified via just fetch-reference and just validate-references before being committed to a KB entry — treat this report as a well-sourced lead set, not pre-verified curation-ready evidence.

Primary Ciliary Dyskinesia 47 and Lissencephaly

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1. Disease Information

2. Etiology

3. Phenotypes

Respiratory phenotype (present in all 7 reported patients)

Neurological/CNS phenotype (present in all 7 reported patients)

4. Genetic/Molecular Information

5. Environmental Information

6. Mechanism / Pathophysiology

7. Anatomical Structures Affected

8. Temporal Development

9. Inheritance and Population

10. Diagnostics

11. Outcome/Prognosis

12. Treatment

13. Prevention

14. Other Species / Natural Disease

15. Model Organisms

Summary of Key Ontology Term Suggestions (to be independently OAK-verified before KB entry)

Key Primary Citations (PMIDs)