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6
Pathophys.
6
Phenotypes
3
Gaps
7
Pathograph
1
Genes
4
Medical Actions
7
References
1
Deep Research
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Discussions and Knowledge Gaps

3
Which SRPX2 variants have sufficient modern segregation, population, functional, and replication evidence to support a single disease entry with speech-epilepsy and bilateral perisylvian PMG branches?
KNOWLEDGE GAP OPEN gap_srpx2_variant_causality_and_lumping
The original abstracts support reported N327S and Y72S branches, but the Falcon report flagged later concern about variant-specific causality for N327S. For curation, this means SRPX2 should stay as a coherent mechanism-bound entry while variant-level confidence and subtype branching remain open until modern ClinVar/gnomAD/segregation and rescue evidence are reviewed.
Proposed experiments
SRPX2 variant reclassification and rescue panel
variant reclassification and functional rescue experiment
exp_srpx2_variant_reclassification_panel
Reassess reported SRPX2 variants with current population frequencies, segregation, X-inactivation data, protein-processing assays, and standardized rescue of SRPX2 knockdown or knockout phenotypes. Include N327S, Y72S, nearby first-sushi-domain variants, and matched benign controls.
Perturbations
SRPX2 variant knock-in or rescue
Introduce or rescue individual SRPX2 variants in a shared assay background to compare protein processing, migration, and tubulin acetylation.
SRPX2 hgnc:30668
Readouts
Protein processing and neuronal migration rescue
neuron migration GO:0001764 ↓ DECREASED protein acetylation GO:0006473 ↕ DYSREGULATED
cell migration assay immunoblot assay
Direction: POSITIVE
Controls
Wild-type SRPX2 rescue
Rescue with wild-type human SRPX2.
Benign variant controls
Variants with population frequency incompatible with disease causality.
Decision criterion
A variant-specific branch is supported only when the variant segregates with disease and reproducibly fails to rescue protein-processing, migration, or tubulin-acetylation phenotypes relative to wild type.
Show evidence (2 references)
PMID:16497722 SUPPORT Human Clinical
"A second mutation (Y72S) was identified within the first sushi domain of SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his female relatives with mild MR or unaffected carrier status."
Shows variable expression or carrier status within the reported PMG branch, motivating careful variant-level interpretation.
PMID:17942002 SUPPORT Other
"The R75K substitution occurred in the first sushi domain of SRPX2, only three amino acid residues away from a previously reported disease-causing mutation (Y72S)."
Supports focusing variant interpretation on the first sushi domain while keeping functional consequences open.
Do SRPX2 migration, tubulin-acetylation, and epileptiform phenotypes observed in rat in utero silencing translate to human perisylvian cortical development and patient-relevant speech-cortex biology?
HUMAN MODEL MISMATCH OPEN gap_srpx2_human_model_translatability
The strongest mechanistic evidence is a rodent in utero silencing and rescue model. The Falcon report did not identify direct SRPX2 patient iPSC or organoid evidence. Human cortical organoids cannot fully model speech behavior, but they can test whether SRPX2 variants perturb human cortical neuronal migration, tubulin acetylation, and perisylvian-like cortical organization before seizure phenotypes are inferred.
Proposed experiments
SRPX2 isogenic cortical-organoid migration and tubulin-acetylation experiment
isogenic cortical organoid migration experiment
exp_srpx2_isogenic_cortical_organoid_migration_acetylation
Generate patient-derived or engineered human cortical organoids carrying SRPX2 N327S, Y72S, loss-of-function, and corrected alleles, then compare cortical neuron migration, alpha-tubulin acetylation, SRPX2/uPAR pathway readouts, and network activity against the rat in utero model.
Model systems
SRPX2 human iPSC-derived cortical organoid
Human cortical organoid or cortical assembloid model with neural progenitors and migrating cortical neurons, used for migration and network-readout assays rather than speech-behavior phenotyping.
cerebral cortex UBERON:0000956
cortical neuron CL:0000540 neural progenitor cell CL:0011020
Perturbations
SRPX2 variant correction or knock-in
Correct patient variants or introduce reported SRPX2 variants into an isogenic human iPSC background.
SRPX2 hgnc:30668
Readouts
Neuronal migration and alpha-tubulin acetylation
neuron migration GO:0001764 ↓ DECREASED protein acetylation GO:0006473 ↕ DYSREGULATED
live-cell imaging assay immunostaining
Direction: POSITIVE
Network excitability readout
trans-synaptic signaling GO:0099537 ↕ DYSREGULATED
multielectrode array recording
Direction: POSITIVE
Controls
Isogenic corrected organoids
Matched organoids in which the SRPX2 variant is corrected.
Isogenic knock-in organoids
Wild-type-background organoids carrying the introduced SRPX2 variant.
Decision criterion
Human translation is supported if SRPX2 mutant organoids show migration and tubulin-acetylation defects matching the rat model and rescued by variant correction or wild-type SRPX2. The seizure branch remains inferential unless network hyperexcitability is reproducibly detected.
Show evidence (2 references)
PMID:23831613 SUPPORT Model Organism
"Using an in utero Srpx2 silencing approach, we show that SRPX2 influences neuronal migration in the developing rat cerebral cortex."
Identifies the model-organism mechanism whose human translation remains open.
PMID:28111201 SUPPORT Other
"Recent work has uncovered critical cellular and molecular differences between cortical development in humans and mice, further underscoring the need to develop human model systems."
Supports explicit human/model mismatch handling for cortical-development mechanisms.
Does tubacin prevention of rat Srpx2-silencing phenotypes identify a realistic therapeutic mechanism for human SRPX2 disease, or only a developmental proof of principle?
KNOWLEDGE GAP OPEN gap_srpx2_tubacin_preclinical_translation
Tubacin prevention is mechanistically important, but it is prenatal, model-organism, pathway-level evidence. It should not be curated as a disease-modifying human treatment without dose, timing, safety, specificity, and human-cell rescue evidence.
Proposed experiments
SRPX2 tubacin rescue window and specificity experiment
preclinical rescue-window experiment
exp_srpx2_tubacin_human_cell_rescue_window
Test tubacin and more selective tubulin-acetylation modulators in SRPX2 human neural progenitor and cortical organoid models across developmental windows, measuring migration rescue, alpha-tubulin acetylation, off-target transcriptional effects, and network activity.
Readouts
Rescue and toxicity readouts
neuron migration GO:0001764 ↓ DECREASED protein acetylation GO:0006473 ↕ DYSREGULATED
migration assay cell viability assay
Direction: POSITIVE
Controls
Vehicle-treated mutant and corrected controls
Matched controls to distinguish rescue from nonspecific toxicity.
Decision criterion
Therapeutic plausibility increases only if a safe exposure window rescues human-cell migration and acetylation defects without broad toxicity or nonspecific developmental disruption.
Show evidence (1 reference)
PMID:23831613 SUPPORT Model Organism
"The neuronal migration defects and the post-natal epileptic consequences were prevented early in embryos by maternal administration of tubulin deacetylase inhibitor tubacin."
Supports tubacin as a preclinical pathway probe, not a current human therapy.

Pathophysiology

6
SRPX2 Missense Variation and Protein Processing Defect
Reported SRPX2 missense variants affect a secreted sushi-repeat protein expressed in neurons of the human brain, including the rolandic area. The N327S variant was reported with rolandic seizures, oral/speech dyspraxia, and intellectual disability, while Y72S was reported in a male with rolandic seizures and bilateral perisylvian polymicrogyria. Cultured-cell data suggest altered intracellular processing and protein misfolding.
neuron CL:0000540
SRPX2 hgnc:30668
protein folding GO:0006457 ↕ DYSREGULATED protein N-linked glycosylation GO:0006487 ↕ DYSREGULATED
Show evidence (3 references)
PMID:16497722 SUPPORT Human Clinical
"We have identified the Xq22 gene SRPX2 as being responsible for rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR)."
Establishes the original reported SRPX2 association with the speech-epilepsy branch.
PMID:16497722 SUPPORT Human Clinical
"A second mutation (Y72S) was identified within the first sushi domain of SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his female relatives with mild MR or unaffected carrier status."
Supports including bilateral perisylvian polymicrogyria within the SRPX2-related boundary.
PMID:16497722 SUPPORT In Vitro
"In cultured cells, both mutations were associated with altered patterns of intracellular processing, suggesting protein misfolding."
Links the reported variants to altered protein handling in cells.
FOXP2-SRPX2-uPAR Speech-Cortex Regulatory Network Perturbation
FOXP2 directly represses SRPX2 and uPAR promoter activity, and SRPX2-driven mechanisms involve modified interaction with uPAR. This branch does not make FOXP2 disease part of the SRPX2 entry; it records the regulatory network that helps explain why SRPX2 phenotypes center on speech-related rolandic/sylvian cortex.
SRPX2 hgnc:30668
regulation of DNA-templated transcription GO:0006355 ↕ DYSREGULATED cell adhesion GO:0007155 ↕ DYSREGULATED
Show evidence (3 references)
PMID:20858596 SUPPORT In Vitro
"Pathophysiological mechanisms driven by SRPX2 involve modified interaction with the plasminogen activator receptor (uPAR)."
Supports the SRPX2/uPAR interaction branch.
PMID:20858596 SUPPORT In Vitro
"identified specific efficient FOXP2-binding sites in each of the promoter regions of SRPX2 and uPAR."
Supports direct transcriptional regulation of SRPX2 and uPAR by FOXP2.
PMID:20858596 SUPPORT In Vitro
"Luciferase reporter assays demonstrated that FOXP2 expression yielded a marked inhibition of SRPX2 (80.2%) and uPAR (77.5%) promoter activity."
Quantitatively supports FOXP2-mediated repression of the SRPX2/uPAR network.
Tubulin Acetylation and Neuronal Migration Defect
In utero Srpx2 silencing in rat cortex impairs neuronal migration, and wild-type but not mutant human SRPX2 rescues the migration phenotype while increasing alpha-tubulin acetylation. This is the clearest module-conformant branch and links SRPX2 to the microtubule-dependent neuronal migration module rather than to a generic epilepsy module.
cortical neuron CL:0000540
neuron migration GO:0001764 ↓ DECREASED microtubule cytoskeleton organization GO:0000226 ↕ DYSREGULATED protein acetylation GO:0006473 ↕ DYSREGULATED
Show evidence (2 references)
PMID:23831613 SUPPORT Model Organism
"Using an in utero Srpx2 silencing approach, we show that SRPX2 influences neuronal migration in the developing rat cerebral cortex."
Directly supports SRPX2-dependent neuronal migration in developing cortex.
PMID:23831613 SUPPORT Model Organism
"Wild-type, but not the mutant human SRPX2 proteins, rescued the neuronal migration phenotype caused by Srpx2 silencing in utero, and increased alpha-tubulin acetylation."
Connects mutant SRPX2, neuronal migration rescue failure, and alpha-tubulin acetylation.
Perisylvian Cortical Organization Failure
The cortical-malformation branch is most specific for bilateral perisylvian polymicrogyria, a migration-related malformation affecting rolandic/sylvian speech areas. This endpoint justifies retaining PMG within the SRPX2 entry only when connected to the same speech-cortex migration skeleton.
cortical neuron CL:0000540
cerebral cortex development GO:0021987 ↕ DYSREGULATED neuron migration GO:0001764 ↓ DECREASED
cerebral cortex UBERON:0000956
Show evidence (2 references)
PMID:16497722 SUPPORT Human Clinical
"A second mutation (Y72S) was identified within the first sushi domain of SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his female relatives with mild MR or unaffected carrier status."
Supports bilateral perisylvian polymicrogyria as the structural branch.
PMID:36211152 SUPPORT Other
"Polymicrogyria (PMG) is a relatively common complex malformation with cortical development, characterized by an exorbitant number of abnormally tiny gyri separated by shallow sulci. It is a neuronal migration disorder."
Supports treating PMG as a neuronal-migration-related cortical malformation.
Speech and Oromotor Impairment
The rolandic/sylvian and perisylvian cortical involvement produces speech and oral motor impairment, including oral/speech dyspraxia, delayed or impaired language, and variable cognitive disability.
nervous system development GO:0007399 ↕ DYSREGULATED
cerebral cortex UBERON:0000956
Show evidence (1 reference)
PMID:16497722 SUPPORT Human Clinical
"The involvement of SRPX2 in these disorders suggests an important role for SRPX2 in the perisylvian region critical for language and cognitive development."
Links SRPX2 to perisylvian language and cognitive development.
Postnatal Epileptiform Activity
Disrupted SRPX2-dependent cortical development can be followed by postnatal epileptiform activity. This node records the seizure/epileptiform endpoint without asserting a specific ion-channel or excitation-inhibition mechanism.
cortical neuron CL:0000540
nervous system development GO:0007399 ↕ DYSREGULATED
Show evidence (2 references)
PMID:23831613 SUPPORT Model Organism
"Following in utero Srpx2 silencing, spontaneous epileptiform activity was recorded post-natally."
Supports epileptiform activity as a downstream consequence of in utero Srpx2 perturbation.
PMID:19682046 SUPPORT Other
"Recent reports on the involvement of the SRPX2 and ELP4 genes with possible roles in cell motility, migration, and adhesion have provided first insights into the complex molecular bases of childhood focal epilepsies."
Review-level support connects SRPX2-related motility/migration biology to childhood focal epilepsy mechanisms.

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for SRPX2-related Speech-Epilepsy-Polymicrogyria Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.

Phenotypes

6
Nervous System 3
Rolandic Seizures / Focal Epilepsy Seizure HP:0001250
Onset: CHILDHOOD
Show evidence (1 reference)
PMID:16497722 SUPPORT Human Clinical
"We have identified the Xq22 gene SRPX2 as being responsible for rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR)."
Supports rolandic seizures as part of the reported SRPX2 phenotype.
Speech Apraxia Speech apraxia HP:0011098
Show evidence (1 reference)
PMID:16497722 SUPPORT Human Clinical
"rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR)."
Supports speech dyspraxia as a core feature.
Intellectual Disability Intellectual disability HP:0001249
Show evidence (1 reference)
PMID:16497722 SUPPORT Human Clinical
"rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR)."
Supports intellectual disability using the source's historical term.
Other 3
EEG With Centrotemporal Epileptiform Discharges EEG with centrotemporal epileptiform discharges HP:0033721
Show evidence (1 reference)
PMID:19682046 SUPPORT Other
"the benign childhood epilepsy with centrotemporal spikes (BCECTS) or benign rolandic epilepsy, are different entities that are considered as part of a single continuous spectrum of disorders."
Supports the centrotemporal spike-wave context of the childhood focal epilepsy spectrum.
Oromotor Apraxia Oromotor apraxia HP:0007301
Show evidence (1 reference)
PMID:16497722 SUPPORT Human Clinical
"rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR)."
Supports oral dyspraxia as an oromotor phenotype.
Bilateral Perisylvian Polymicrogyria Bilateral perisylvian polymicrogyria HP:0032407
Show evidence (1 reference)
PMID:16497722 SUPPORT Human Clinical
"bilateral perisylvian polymicrogyria and his female relatives with mild MR or unaffected carrier status."
Supports bilateral perisylvian polymicrogyria in the reported SRPX2 structural branch.
🧬

Genetic Associations

1
SRPX2 (Reported causal variants with unresolved variant-specific confidence)
Gene: SRPX2 hgnc:30668
Show evidence (2 references)
PMID:16497722 SUPPORT Human Clinical
"We have identified the Xq22 gene SRPX2 as being responsible for rolandic seizures (RSs) associated with oral and speech dyspraxia and mental retardation (MR)."
Supports the reported SRPX2 gene-disease association for the speech-epilepsy branch.
PMID:16497722 SUPPORT Human Clinical
"A second mutation (Y72S) was identified within the first sushi domain of SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his female relatives with mild MR or unaffected carrier status."
Supports the reported SRPX2 gene-disease association for the PMG branch.
💊

Medical Actions

4
Anti-Seizure Medication
Action: Anticonvulsant Therapy NCIT:C64172
Standard seizure management is symptomatic; tubacin evidence remains preclinical and does not establish a human therapy.
Speech Therapy
Action: speech therapy MAXO:0000930
Supportive speech-language therapy is relevant for speech apraxia and speech/language impairment.
Occupational Therapy
Action: occupational therapy MAXO:0001351
Supportive occupational therapy may be appropriate for associated motor, developmental, or functional impairment.
Genetic Counseling
Action: Genetic Counseling NCIT:C15240
X-linked inheritance, variable female expression, and uncertain variant-specific confidence make genetic counseling important after a reported SRPX2 variant is found.
{ }

Source YAML

click to show
name: SRPX2-related Speech-Epilepsy-Polymicrogyria
creation_date: "2026-06-12T03:31:46Z"
category: Mendelian
description: >-
  SRPX2-related speech-epilepsy-polymicrogyria is an X-linked
  neurodevelopmental disorder boundary in which reported SRPX2 variants affect
  rolandic/sylvian speech-cortex function and development. The entry lumps
  rolandic epilepsy with oral/speech dyspraxia and the bilateral perisylvian
  polymicrogyria presentation because the shared skeleton is coherent:
  SRPX2-dependent protein processing and SRPX2/uPAR network function converge
  on neuronal migration, tubulin acetylation, perisylvian cortical organization,
  and later epileptiform activity. It should not be expanded to all rolandic
  epilepsy, all developmental speech disorder, or all polymicrogyria.
parents:
- Rolandic epilepsy
- Polymicrogyria
- speech disorder
- malformation of cortical development
notes: >-
  MONDO:0015587 labels rolandic epilepsy-speech dyspraxia syndrome, but no
  disease_term is assigned because this curation intentionally includes the
  SRPX2-associated bilateral perisylvian polymicrogyria boundary only where the
  same SRPX2 speech-cortex migration mechanism applies. The ontology term does
  not define the disease boundary.
references:
- reference: PMID:16497722
  title: SRPX2 mutations in disorders of language cortex and cognition.
- reference: PMID:23831613
  title: Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
- reference: PMID:20858596
  title: "Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex."
- reference: PMID:17942002
  title: Molecular evolution of the human SRPX2 gene that causes brain disorders of the Rolandic and Sylvian speech areas.
- reference: PMID:19682046
  title: "From rolandic epilepsy to continuous spike-and-waves during sleep and Landau-Kleffner syndromes: insights into possible genetic factors."
- reference: PMID:36211152
  title: The Genetic Landscape of Polymicrogyria.
- reference: PMID:28111201
  title: Human iPSC-Derived Cerebral Organoids Model Cellular Features of Lissencephaly and Reveal Prolonged Mitosis of Outer Radial Glia.
pathophysiology:
- name: SRPX2 Missense Variation and Protein Processing Defect
  description: >-
    Reported SRPX2 missense variants affect a secreted sushi-repeat protein
    expressed in neurons of the human brain, including the rolandic area. The
    N327S variant was reported with rolandic seizures, oral/speech dyspraxia,
    and intellectual disability, while Y72S was reported in a male with
    rolandic seizures and bilateral perisylvian polymicrogyria. Cultured-cell
    data suggest altered intracellular processing and protein misfolding.
  role: trigger
  genes:
  - preferred_term: SRPX2
    term:
      id: hgnc:30668
      label: SRPX2
  cell_types:
  - preferred_term: neuron
    term:
      id: CL:0000540
      label: neuron
  biological_processes:
  - preferred_term: protein folding
    term:
      id: GO:0006457
      label: protein folding
    modifier: DYSREGULATED
  - preferred_term: protein N-linked glycosylation
    term:
      id: GO:0006487
      label: protein N-linked glycosylation
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We have identified the Xq22 gene SRPX2 as being responsible for rolandic
      seizures (RSs) associated with oral and speech dyspraxia and mental
      retardation (MR).
    explanation: >-
      Establishes the original reported SRPX2 association with the
      speech-epilepsy branch.
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      A second mutation (Y72S) was identified within the first sushi domain of
      SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his
      female relatives with mild MR or unaffected carrier status.
    explanation: >-
      Supports including bilateral perisylvian polymicrogyria within the
      SRPX2-related boundary.
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      In cultured cells, both mutations were associated with altered patterns of
      intracellular processing, suggesting protein misfolding.
    explanation: >-
      Links the reported variants to altered protein handling in cells.
  downstream:
  - target: FOXP2-SRPX2-uPAR Speech-Cortex Regulatory Network Perturbation
    description: >-
      SRPX2 participates in a speech-related regulatory network involving FOXP2
      and uPAR.
  - target: Tubulin Acetylation and Neuronal Migration Defect
    description: >-
      SRPX2 loss or mutant SRPX2 impairs cortical neuronal migration and
      alpha-tubulin acetylation in a developmental model.

- name: FOXP2-SRPX2-uPAR Speech-Cortex Regulatory Network Perturbation
  description: >-
    FOXP2 directly represses SRPX2 and uPAR promoter activity, and SRPX2-driven
    mechanisms involve modified interaction with uPAR. This branch does not
    make FOXP2 disease part of the SRPX2 entry; it records the regulatory
    network that helps explain why SRPX2 phenotypes center on speech-related
    rolandic/sylvian cortex.
  role: modifier
  genes:
  - preferred_term: SRPX2
    term:
      id: hgnc:30668
      label: SRPX2
  biological_processes:
  - preferred_term: regulation of DNA-templated transcription
    term:
      id: GO:0006355
      label: regulation of DNA-templated transcription
    modifier: DYSREGULATED
  - preferred_term: cell adhesion
    term:
      id: GO:0007155
      label: cell adhesion
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:20858596
    reference_title: "Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      Pathophysiological mechanisms driven by SRPX2 involve modified interaction
      with the plasminogen activator receptor (uPAR).
    explanation: >-
      Supports the SRPX2/uPAR interaction branch.
  - reference: PMID:20858596
    reference_title: "Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      identified specific efficient FOXP2-binding sites in each of the promoter
      regions of SRPX2 and uPAR.
    explanation: >-
      Supports direct transcriptional regulation of SRPX2 and uPAR by FOXP2.
  - reference: PMID:20858596
    reference_title: "Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex."
    supports: SUPPORT
    evidence_source: IN_VITRO
    snippet: >-
      Luciferase reporter assays demonstrated that FOXP2 expression yielded a
      marked inhibition of SRPX2 (80.2%) and uPAR (77.5%) promoter activity.
    explanation: >-
      Quantitatively supports FOXP2-mediated repression of the SRPX2/uPAR
      network.
  downstream:
  - target: Tubulin Acetylation and Neuronal Migration Defect

- name: Tubulin Acetylation and Neuronal Migration Defect
  description: >-
    In utero Srpx2 silencing in rat cortex impairs neuronal migration, and
    wild-type but not mutant human SRPX2 rescues the migration phenotype while
    increasing alpha-tubulin acetylation. This is the clearest module-conformant
    branch and links SRPX2 to the microtubule-dependent neuronal migration
    module rather than to a generic epilepsy module.
  conforms_to: microtubule_dependent_neuronal_migration_failure#Microtubule-Based Neuronal Motility Failure
  role: central_effector
  cell_types:
  - preferred_term: cortical neuron
    term:
      id: CL:0000540
      label: neuron
  biological_processes:
  - preferred_term: neuron migration
    term:
      id: GO:0001764
      label: neuron migration
    modifier: DECREASED
  - preferred_term: microtubule cytoskeleton organization
    term:
      id: GO:0000226
      label: microtubule cytoskeleton organization
    modifier: DYSREGULATED
  - preferred_term: protein acetylation
    term:
      id: GO:0006473
      label: protein acetylation
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:23831613
    reference_title: Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Using an in utero Srpx2 silencing approach, we show that SRPX2 influences
      neuronal migration in the developing rat cerebral cortex.
    explanation: >-
      Directly supports SRPX2-dependent neuronal migration in developing cortex.
  - reference: PMID:23831613
    reference_title: Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Wild-type, but not the mutant human SRPX2 proteins, rescued the neuronal
      migration phenotype caused by Srpx2 silencing in utero, and increased
      alpha-tubulin acetylation.
    explanation: >-
      Connects mutant SRPX2, neuronal migration rescue failure, and
      alpha-tubulin acetylation.
  downstream:
  - target: Perisylvian Cortical Organization Failure
  - target: Postnatal Epileptiform Activity

- name: Perisylvian Cortical Organization Failure
  description: >-
    The cortical-malformation branch is most specific for bilateral
    perisylvian polymicrogyria, a migration-related malformation affecting
    rolandic/sylvian speech areas. This endpoint justifies retaining PMG within
    the SRPX2 entry only when connected to the same speech-cortex migration
    skeleton.
  conforms_to: microtubule_dependent_neuronal_migration_failure#Cortical Dyslamination and Neuronal Ectopia
  role: outcome
  locations:
  - preferred_term: cerebral cortex
    term:
      id: UBERON:0000956
      label: cerebral cortex
  cell_types:
  - preferred_term: cortical neuron
    term:
      id: CL:0000540
      label: neuron
  biological_processes:
  - preferred_term: cerebral cortex development
    term:
      id: GO:0021987
      label: cerebral cortex development
    modifier: DYSREGULATED
  - preferred_term: neuron migration
    term:
      id: GO:0001764
      label: neuron migration
    modifier: DECREASED
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      A second mutation (Y72S) was identified within the first sushi domain of
      SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his
      female relatives with mild MR or unaffected carrier status.
    explanation: >-
      Supports bilateral perisylvian polymicrogyria as the structural branch.
  - reference: PMID:36211152
    reference_title: The Genetic Landscape of Polymicrogyria.
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Polymicrogyria (PMG) is a relatively common complex malformation with
      cortical development, characterized by an exorbitant number of abnormally
      tiny gyri separated by shallow sulci. It is a neuronal migration disorder.
    explanation: >-
      Supports treating PMG as a neuronal-migration-related cortical
      malformation.
  downstream:
  - target: Speech and Oromotor Impairment
  - target: Postnatal Epileptiform Activity

- name: Speech and Oromotor Impairment
  description: >-
    The rolandic/sylvian and perisylvian cortical involvement produces speech
    and oral motor impairment, including oral/speech dyspraxia, delayed or
    impaired language, and variable cognitive disability.
  role: outcome
  locations:
  - preferred_term: cerebral cortex
    term:
      id: UBERON:0000956
      label: cerebral cortex
  biological_processes:
  - preferred_term: nervous system development
    term:
      id: GO:0007399
      label: nervous system development
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      The involvement of SRPX2 in these disorders suggests an important role for
      SRPX2 in the perisylvian region critical for language and cognitive
      development.
    explanation: >-
      Links SRPX2 to perisylvian language and cognitive development.

- name: Postnatal Epileptiform Activity
  description: >-
    Disrupted SRPX2-dependent cortical development can be followed by postnatal
    epileptiform activity. This node records the seizure/epileptiform endpoint
    without asserting a specific ion-channel or excitation-inhibition mechanism.
  role: outcome
  cell_types:
  - preferred_term: cortical neuron
    term:
      id: CL:0000540
      label: neuron
  biological_processes:
  - preferred_term: nervous system development
    term:
      id: GO:0007399
      label: nervous system development
    modifier: DYSREGULATED
  evidence:
  - reference: PMID:23831613
    reference_title: Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Following in utero Srpx2 silencing, spontaneous epileptiform activity was
      recorded post-natally.
    explanation: >-
      Supports epileptiform activity as a downstream consequence of in utero
      Srpx2 perturbation.
  - reference: PMID:19682046
    reference_title: "From rolandic epilepsy to continuous spike-and-waves during sleep and Landau-Kleffner syndromes: insights into possible genetic factors."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Recent reports on the involvement of the SRPX2 and ELP4 genes with
      possible roles in cell motility, migration, and adhesion have provided
      first insights into the complex molecular bases of childhood focal
      epilepsies.
    explanation: >-
      Review-level support connects SRPX2-related motility/migration biology to
      childhood focal epilepsy mechanisms.
phenotypes:
- name: Rolandic Seizures / Focal Epilepsy
  description: >-
    Reported SRPX2 disease includes rolandic seizures and childhood focal
    epilepsy-spectrum presentations.
  phenotype_term:
    preferred_term: Seizure
    term:
      id: HP:0001250
      label: Seizure
    onset:
      onset_category: CHILDHOOD
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We have identified the Xq22 gene SRPX2 as being responsible for rolandic
      seizures (RSs) associated with oral and speech dyspraxia and mental
      retardation (MR).
    explanation: >-
      Supports rolandic seizures as part of the reported SRPX2 phenotype.
- name: EEG With Centrotemporal Epileptiform Discharges
  description: >-
    Centrotemporal spike-wave EEG features are part of the broader rolandic
    epilepsy spectrum relevant to SRPX2 presentations.
  phenotype_term:
    preferred_term: EEG with centrotemporal epileptiform discharges
    term:
      id: HP:0033721
      label: EEG with centrotemporal epileptiform discharges
  evidence:
  - reference: PMID:19682046
    reference_title: "From rolandic epilepsy to continuous spike-and-waves during sleep and Landau-Kleffner syndromes: insights into possible genetic factors."
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      the benign childhood epilepsy with centrotemporal spikes (BCECTS) or
      benign rolandic epilepsy, are different entities that are considered as
      part of a single continuous spectrum of disorders.
    explanation: >-
      Supports the centrotemporal spike-wave context of the childhood focal
      epilepsy spectrum.
- name: Speech Apraxia
  description: >-
    Speech dyspraxia is central to the speech-epilepsy branch of reported
    SRPX2 disease.
  phenotype_term:
    preferred_term: Speech apraxia
    term:
      id: HP:0011098
      label: Speech apraxia
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      rolandic seizures (RSs) associated with oral and speech dyspraxia and
      mental retardation (MR).
    explanation: >-
      Supports speech dyspraxia as a core feature.
- name: Oromotor Apraxia
  description: >-
    Oral dyspraxia is described with the rolandic seizure phenotype.
  phenotype_term:
    preferred_term: Oromotor apraxia
    term:
      id: HP:0007301
      label: Oromotor apraxia
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      rolandic seizures (RSs) associated with oral and speech dyspraxia and
      mental retardation (MR).
    explanation: >-
      Supports oral dyspraxia as an oromotor phenotype.
- name: Bilateral Perisylvian Polymicrogyria
  description: >-
    The structural cortical malformation branch is bilateral perisylvian
    polymicrogyria affecting speech-related cortex.
  phenotype_term:
    preferred_term: Bilateral perisylvian polymicrogyria
    term:
      id: HP:0032407
      label: Bilateral perisylvian polymicrogyria
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      bilateral perisylvian polymicrogyria and his female relatives with mild MR
      or unaffected carrier status.
    explanation: >-
      Supports bilateral perisylvian polymicrogyria in the reported SRPX2
      structural branch.
- name: Intellectual Disability
  description: >-
    Cognitive impairment is variable; the original abstract uses historical
    terminology for intellectual disability.
  phenotype_term:
    preferred_term: Intellectual disability
    term:
      id: HP:0001249
      label: Intellectual disability
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      rolandic seizures (RSs) associated with oral and speech dyspraxia and
      mental retardation (MR).
    explanation: >-
      Supports intellectual disability using the source's historical term.
genetic:
- name: SRPX2
  association: Reported causal variants with unresolved variant-specific confidence
  gene_term:
    preferred_term: SRPX2
    term:
      id: hgnc:30668
      label: SRPX2
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      We have identified the Xq22 gene SRPX2 as being responsible for rolandic
      seizures (RSs) associated with oral and speech dyspraxia and mental
      retardation (MR).
    explanation: >-
      Supports the reported SRPX2 gene-disease association for the
      speech-epilepsy branch.
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      A second mutation (Y72S) was identified within the first sushi domain of
      SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his
      female relatives with mild MR or unaffected carrier status.
    explanation: >-
      Supports the reported SRPX2 gene-disease association for the PMG branch.
treatments:
- name: Anti-Seizure Medication
  description: >-
    Standard seizure management is symptomatic; tubacin evidence remains
    preclinical and does not establish a human therapy.
  treatment_term:
    preferred_term: Anticonvulsant Therapy
    term:
      id: NCIT:C64172
      label: Anticonvulsant Therapy
- name: Speech Therapy
  description: >-
    Supportive speech-language therapy is relevant for speech apraxia and
    speech/language impairment.
  treatment_term:
    preferred_term: speech therapy
    term:
      id: MAXO:0000930
      label: speech therapy
- name: Occupational Therapy
  description: >-
    Supportive occupational therapy may be appropriate for associated motor,
    developmental, or functional impairment.
  treatment_term:
    preferred_term: occupational therapy
    term:
      id: MAXO:0001351
      label: occupational therapy
- name: Genetic Counseling
  description: >-
    X-linked inheritance, variable female expression, and uncertain
    variant-specific confidence make genetic counseling important after a
    reported SRPX2 variant is found.
  treatment_term:
    preferred_term: Genetic Counseling
    term:
      id: NCIT:C15240
      label: Genetic Counseling
discussions:
- discussion_id: gap_srpx2_variant_causality_and_lumping
  prompt: >-
    Which SRPX2 variants have sufficient modern segregation, population,
    functional, and replication evidence to support a single disease entry with
    speech-epilepsy and bilateral perisylvian PMG branches?
  kind: KNOWLEDGE_GAP
  status: OPEN
  attaches_to:
  - pathophysiology#SRPX2 Missense Variation and Protein Processing Defect
  - pathophysiology#Perisylvian Cortical Organization Failure
  rationale: >-
    The original abstracts support reported N327S and Y72S branches, but the
    Falcon report flagged later concern about variant-specific causality for
    N327S. For curation, this means SRPX2 should stay as a coherent
    mechanism-bound entry while variant-level confidence and subtype branching
    remain open until modern ClinVar/gnomAD/segregation and rescue evidence are
    reviewed.
  evidence:
  - reference: PMID:16497722
    reference_title: SRPX2 mutations in disorders of language cortex and cognition.
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: >-
      A second mutation (Y72S) was identified within the first sushi domain of
      SRPX2 in a male with RSs and bilateral perisylvian polymicrogyria and his
      female relatives with mild MR or unaffected carrier status.
    explanation: >-
      Shows variable expression or carrier status within the reported PMG
      branch, motivating careful variant-level interpretation.
  - reference: PMID:17942002
    reference_title: Molecular evolution of the human SRPX2 gene that causes brain disorders of the Rolandic and Sylvian speech areas.
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      The R75K substitution occurred in the first sushi domain of SRPX2, only
      three amino acid residues away from a previously reported disease-causing
      mutation (Y72S).
    explanation: >-
      Supports focusing variant interpretation on the first sushi domain while
      keeping functional consequences open.
  proposed_experiments:
  - experiment_id: exp_srpx2_variant_reclassification_panel
    name: SRPX2 variant reclassification and rescue panel
    description: >-
      Reassess reported SRPX2 variants with current population frequencies,
      segregation, X-inactivation data, protein-processing assays, and
      standardized rescue of SRPX2 knockdown or knockout phenotypes. Include
      N327S, Y72S, nearby first-sushi-domain variants, and matched benign
      controls.
    experiment_type:
      preferred_term: variant reclassification and functional rescue experiment
    perturbations:
    - name: SRPX2 variant knock-in or rescue
      target: pathophysiology#SRPX2 Missense Variation and Protein Processing Defect
      genes:
      - preferred_term: SRPX2
        term:
          id: hgnc:30668
          label: SRPX2
      description: >-
        Introduce or rescue individual SRPX2 variants in a shared assay
        background to compare protein processing, migration, and tubulin
        acetylation.
    readouts:
    - name: Protein processing and neuronal migration rescue
      target: pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
      biological_processes:
      - preferred_term: neuron migration
        term:
          id: GO:0001764
          label: neuron migration
        modifier: DECREASED
      - preferred_term: protein acetylation
        term:
          id: GO:0006473
          label: protein acetylation
        modifier: DYSREGULATED
      assays:
      - preferred_term: cell migration assay
      - preferred_term: immunoblot assay
      direction: POSITIVE
    controls:
    - name: Wild-type SRPX2 rescue
      description: Rescue with wild-type human SRPX2.
    - name: Benign variant controls
      description: Variants with population frequency incompatible with disease causality.
    decision_criterion: >-
      A variant-specific branch is supported only when the variant segregates
      with disease and reproducibly fails to rescue protein-processing,
      migration, or tubulin-acetylation phenotypes relative to wild type.
    would_support:
    - pathophysiology#SRPX2 Missense Variation and Protein Processing Defect
    - pathophysiology#Tubulin Acetylation and Neuronal Migration Defect

- discussion_id: gap_srpx2_human_model_translatability
  prompt: >-
    Do SRPX2 migration, tubulin-acetylation, and epileptiform phenotypes
    observed in rat in utero silencing translate to human perisylvian cortical
    development and patient-relevant speech-cortex biology?
  kind: HUMAN_MODEL_MISMATCH
  status: OPEN
  attaches_to:
  - pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
  - pathophysiology#Perisylvian Cortical Organization Failure
  - pathophysiology#Postnatal Epileptiform Activity
  rationale: >-
    The strongest mechanistic evidence is a rodent in utero silencing and
    rescue model. The Falcon report did not identify direct SRPX2 patient iPSC
    or organoid evidence. Human cortical organoids cannot fully model speech
    behavior, but they can test whether SRPX2 variants perturb human cortical
    neuronal migration, tubulin acetylation, and perisylvian-like cortical
    organization before seizure phenotypes are inferred.
  evidence:
  - reference: PMID:23831613
    reference_title: Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      Using an in utero Srpx2 silencing approach, we show that SRPX2 influences
      neuronal migration in the developing rat cerebral cortex.
    explanation: >-
      Identifies the model-organism mechanism whose human translation remains
      open.
  - reference: PMID:28111201
    reference_title: Human iPSC-Derived Cerebral Organoids Model Cellular Features of Lissencephaly and Reveal Prolonged Mitosis of Outer Radial Glia.
    supports: SUPPORT
    evidence_source: OTHER
    snippet: >-
      Recent work has uncovered critical cellular and molecular differences
      between cortical development in humans and mice, further underscoring the
      need to develop human model systems.
    explanation: >-
      Supports explicit human/model mismatch handling for cortical-development
      mechanisms.
  proposed_experiments:
  - experiment_id: exp_srpx2_isogenic_cortical_organoid_migration_acetylation
    name: SRPX2 isogenic cortical-organoid migration and tubulin-acetylation experiment
    description: >-
      Generate patient-derived or engineered human cortical organoids carrying
      SRPX2 N327S, Y72S, loss-of-function, and corrected alleles, then compare
      cortical neuron migration, alpha-tubulin acetylation, SRPX2/uPAR pathway
      readouts, and network activity against the rat in utero model.
    experiment_type:
      preferred_term: isogenic cortical organoid migration experiment
    model_systems:
    - name: SRPX2 human iPSC-derived cortical organoid
      description: >-
        Human cortical organoid or cortical assembloid model with neural
        progenitors and migrating cortical neurons, used for migration and
        network-readout assays rather than speech-behavior phenotyping.
      experimental_model_type: ORGANOID
      namo_type: namo:Organoid
      organism:
        preferred_term: human
        term:
          id: NCBITaxon:9606
          label: Homo sapiens
      tissue_term:
        preferred_term: cerebral cortex
        term:
          id: UBERON:0000956
          label: cerebral cortex
      cell_types:
      - preferred_term: cortical neuron
        term:
          id: CL:0000540
          label: neuron
      - preferred_term: neural progenitor cell
        term:
          id: CL:0011020
          label: neural progenitor cell
      conditions:
      - SRPX2-related speech-epilepsy-polymicrogyria
      - neuronal migration defect
      - perisylvian polymicrogyria
      cell_source: Patient-derived or CRISPR-engineered human induced pluripotent stem cells
      culture_system: Three-dimensional cortical organoid or cortical assembloid with migration and activity assays
    perturbations:
    - name: SRPX2 variant correction or knock-in
      target: pathophysiology#SRPX2 Missense Variation and Protein Processing Defect
      genes:
      - preferred_term: SRPX2
        term:
          id: hgnc:30668
          label: SRPX2
      description: >-
        Correct patient variants or introduce reported SRPX2 variants into an
        isogenic human iPSC background.
    readouts:
    - name: Neuronal migration and alpha-tubulin acetylation
      target: pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
      biological_processes:
      - preferred_term: neuron migration
        term:
          id: GO:0001764
          label: neuron migration
        modifier: DECREASED
      - preferred_term: protein acetylation
        term:
          id: GO:0006473
          label: protein acetylation
        modifier: DYSREGULATED
      assays:
      - preferred_term: live-cell imaging assay
      - preferred_term: immunostaining
      direction: POSITIVE
    - name: Network excitability readout
      target: pathophysiology#Postnatal Epileptiform Activity
      biological_processes:
      - preferred_term: trans-synaptic signaling
        term:
          id: GO:0099537
          label: trans-synaptic signaling
        modifier: DYSREGULATED
      assays:
      - preferred_term: multielectrode array recording
      direction: POSITIVE
    controls:
    - name: Isogenic corrected organoids
      description: Matched organoids in which the SRPX2 variant is corrected.
    - name: Isogenic knock-in organoids
      description: Wild-type-background organoids carrying the introduced SRPX2 variant.
    decision_criterion: >-
      Human translation is supported if SRPX2 mutant organoids show migration
      and tubulin-acetylation defects matching the rat model and rescued by
      variant correction or wild-type SRPX2. The seizure branch remains
      inferential unless network hyperexcitability is reproducibly detected.
    would_support:
    - pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
    - pathophysiology#Perisylvian Cortical Organization Failure
    - pathophysiology#Postnatal Epileptiform Activity

- discussion_id: gap_srpx2_tubacin_preclinical_translation
  prompt: >-
    Does tubacin prevention of rat Srpx2-silencing phenotypes identify a
    realistic therapeutic mechanism for human SRPX2 disease, or only a
    developmental proof of principle?
  kind: KNOWLEDGE_GAP
  status: OPEN
  attaches_to:
  - pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
  - pathophysiology#Postnatal Epileptiform Activity
  rationale: >-
    Tubacin prevention is mechanistically important, but it is prenatal,
    model-organism, pathway-level evidence. It should not be curated as a
    disease-modifying human treatment without dose, timing, safety, specificity,
    and human-cell rescue evidence.
  evidence:
  - reference: PMID:23831613
    reference_title: Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
    supports: SUPPORT
    evidence_source: MODEL_ORGANISM
    snippet: >-
      The neuronal migration defects and the post-natal epileptic consequences
      were prevented early in embryos by maternal administration of tubulin
      deacetylase inhibitor tubacin.
    explanation: >-
      Supports tubacin as a preclinical pathway probe, not a current human
      therapy.
  proposed_experiments:
  - experiment_id: exp_srpx2_tubacin_human_cell_rescue_window
    name: SRPX2 tubacin rescue window and specificity experiment
    description: >-
      Test tubacin and more selective tubulin-acetylation modulators in SRPX2
      human neural progenitor and cortical organoid models across developmental
      windows, measuring migration rescue, alpha-tubulin acetylation,
      off-target transcriptional effects, and network activity.
    experiment_type:
      preferred_term: preclinical rescue-window experiment
    readouts:
    - name: Rescue and toxicity readouts
      target: pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
      biological_processes:
      - preferred_term: neuron migration
        term:
          id: GO:0001764
          label: neuron migration
        modifier: DECREASED
      - preferred_term: protein acetylation
        term:
          id: GO:0006473
          label: protein acetylation
        modifier: DYSREGULATED
      assays:
      - preferred_term: migration assay
      - preferred_term: cell viability assay
      direction: POSITIVE
    controls:
    - name: Vehicle-treated mutant and corrected controls
      description: Matched controls to distinguish rescue from nonspecific toxicity.
    decision_criterion: >-
      Therapeutic plausibility increases only if a safe exposure window rescues
      human-cell migration and acetylation defects without broad toxicity or
      nonspecific developmental disruption.
    would_support:
    - pathophysiology#Tubulin Acetylation and Neuronal Migration Defect
📚

References & Deep Research

References

7
SRPX2 mutations in disorders of language cortex and cognition.
No top-level findings curated for this source.
Tubacin prevents neuronal migration defects and epileptic activity caused by rat Srpx2 silencing in utero.
No top-level findings curated for this source.
Molecular networks implicated in speech-related disorders: FOXP2 regulates the SRPX2/uPAR complex.
No top-level findings curated for this source.
Molecular evolution of the human SRPX2 gene that causes brain disorders of the Rolandic and Sylvian speech areas.
No top-level findings curated for this source.
From rolandic epilepsy to continuous spike-and-waves during sleep and Landau-Kleffner syndromes: insights into possible genetic factors.
No top-level findings curated for this source.
The Genetic Landscape of Polymicrogyria.
No top-level findings curated for this source.
Human iPSC-Derived Cerebral Organoids Model Cellular Features of Lissencephaly and Reveal Prolonged Mitosis of Outer Radial Glia.
No top-level findings curated for this source.

Deep Research

1
Falcon
SRPX2-related Speech–Epilepsy–Polymicrogyria Boundary (Mendelian) — Research Report
Edison Scientific Literature 24 citations 2026-06-11T20:40:16.812682

SRPX2-related Speech–Epilepsy–Polymicrogyria Boundary (Mendelian) — Research Report

Executive summary

SRPX2-related disease is a rare X-linked neurodevelopmental disorder spectrum centered on (i) focal (rolandic/centrotemporal) epilepsy, (ii) speech/oromotor dyspraxia and language impairment, and (iii) in some individuals, bilateral perisylvian polymicrogyria (PMG) involving speech-related cortical regions. Current mechanistic understanding places SRPX2 within a FOXP2-regulated network and links SRPX2 dysfunction to abnormal neuronal migration and altered tubulin acetylation, with preclinical evidence that pathway-targeted intervention (tubacin) can prevent downstream epileptiform activity in a rodent developmental model. (rudolf2009fromrolandicepilepsy pages 1-2, roll2010molecularnetworksimplicated pages 1-2, salmi2013tubacinpreventsneuronal pages 1-2)

1. Disease information

1.1 Concise overview

“SRPX2-related Speech–Epilepsy–Polymicrogyria Boundary” refers to a clinical continuum spanning rolandic epilepsy with speech dyspraxia (historically termed RESDX in the cited literature) and more overt perisylvian cortical malformation phenotypes (bilateral perisylvian PMG) with epilepsy and neurodevelopmental impairment. (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21)

1.2 Key identifiers (as available in retrieved evidence)

  • Gene: SRPX2 (OMIM 300642) (roll2010molecularnetworksimplicated pages 1-2)
  • Related clinical entities mentioned with OMIM IDs:
  • Rolandic epilepsy–speech dyspraxia (OMIM 300643) (roll2010molecularnetworksimplicated pages 1-2)
  • Bilateral perisylvian polymicrogyria (OMIM 300388) (roll2010molecularnetworksimplicated pages 1-2)
  • OpenTargets disease identifiers returned in this run (aggregated resource):
  • MONDO_0015587: rolandic epilepsy–speech dyspraxia syndrome (OpenTargets Search: -SRPX2)
  • Orphanet 163721: Rolandic epilepsy – speech dyspraxia (OpenTargets Search: -SRPX2)

Not found in retrieved context: ICD-10/ICD-11 codes, MeSH IDs, and a MONDO term explicitly corresponding to the user’s exact label (“speech-epilepsy-polymicrogyria boundary”).

1.3 Synonyms / alternative names (from evidence)

  • Rolandic epilepsy–speech dyspraxia (RESDX / rolandic epilepsy–speech dyspraxia syndrome) (rudolf2009fromrolandicepilepsy pages 1-2, OpenTargets Search: -SRPX2)
  • Bilateral perisylvian polymicrogyria (BPP) / bilateral peri-sylvian PMG (royer2007molecularevolutionof pages 2-3, bernardo2024xlinkedepilepsiesa pages 19-21)
  • X-linked polymicrogyria gene association context (SRPX2 as a prominent X-linked PMG gene) (bernardo2024xlinkedepilepsiesa pages 19-21)

1.4 Evidence source type

The information summarized here is derived from a mix of: * Aggregated resources: OpenTargets disease–gene associations (OpenTargets Search: -SRPX2) * Primary mechanistic research: FOXP2→SRPX2/uPAR regulation (Human Molecular Genetics, 2010) and rodent in utero silencing/rescue studies (Brain, 2013) (roll2010molecularnetworksimplicated pages 1-2, salmi2013tubacinpreventsneuronal pages 1-2) * Clinical/genetics reviews: epilepsy-aphasia/rolandic spectrum and X-linked PMG gene reviews (2009–2024) (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21)

2. Etiology

2.1 Disease causal factors

Primary causal factor: pathogenic variation in SRPX2 (X-linked) in a subset of affected families, with phenotypes involving epilepsy and/or structural malformation of speech cortex. The Brain 2013 paper explicitly frames the prior human findings as: “Two missense mutations in the sushi repeat-containing protein SRPX2 had been previously identified in epileptic disorders with or without structural developmental alteration of the speech cortex.” (salmi2013tubacinpreventsneuronal pages 1-2)

Important nuance: the causal role of at least one reported missense variant (p.N327S) has been questioned due to co-inheritance with another missense change in most affected members of that family. (salmi2013tubacinpreventsneuronal pages 2-2)

2.2 Risk factors

  • Genetic risk factor: SRPX2 missense variants reported in two families/case series, including p.N327S (rolandic epilepsy + verbal dyspraxia) and p.Y72S (bilateral perisylvian PMG), as summarized in the Brain 2013 study (which built a rodent model to assess consequences). (salmi2013tubacinpreventsneuronal pages 2-2)
  • Broader X-linked PMG context: A 2024 narrative review places SRPX2 among the most frequently discussed X-linked PMG genes (with DDX3X and SRPX2 highlighted) and states SRPX2 was initially related to “Rolandic seizures, ID, speech delay, oro-facial dyspraxia, and abnormalities in brain speech areas.” (bernardo2024xlinkedepilepsiesa pages 19-21)

Environmental risk factors / protective factors / gene–environment interactions: Not specifically described in the retrieved SRPX2-focused context. (Evidence gap)

3. Phenotypes

3.1 Core phenotypes (qualitative, given limited frequency data in retrieved texts)

Below are key phenotypes supported by the retrieved literature; quantitative penetrance/frequency estimates for SRPX2-specific cohorts were not available in the extracted passages.

1) Speech and language impairment / dyspraxia * Described as speech delay, verbal/oral dyspraxia, and oro-facial dyspraxia, often central to the syndrome designation. (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21) * Suggested HPO terms (mapping suggestion; not asserted as extracted HPO annotations): * HP:0000750 Speech delay * HP:0002465 Dysarthria * HP:0011445 Oromotor apraxia * HP:0000738 Aphasia / language impairment (broad)

2) Epilepsy (rolandic/centrotemporal focal seizures; spectrum overlap) * SRPX2 is linked to rolandic epilepsy with centrotemporal spikes in the broader rolandic/epilepsy-aphasia spectrum review context. (rudolf2009fromrolandicepilepsy pages 1-2) * Suggested HPO terms: * HP:0001250 Seizures * HP:0002373 Febrile seizures (if present; not established in extracted SRPX2 passages) * HP:0020219 Centrotemporal spikes (EEG) (phenotype representation)

3) Polymicrogyria / bilateral perisylvian polymicrogyria * A disease-associated SRPX2 mutation (Y72) is discussed in the context of “rolandic seizures and bilateral perisylvian polymicrogyria.” (royer2007molecularevolutionof pages 2-3) * Suggested HPO terms: * HP:0002126 Polymicrogyria * HP:0002325 Bilateral perisylvian polymicrogyria

4) Neurodevelopmental impairment / intellectual disability (variable) * A 2009 review states the rolandic epilepsy–speech dyspraxia presentation includes “variable degrees of mental retardation” (historical terminology). (rudolf2009fromrolandicepilepsy pages 1-2) * Suggested HPO terms: * HP:0001249 Intellectual disability * HP:0001263 Global developmental delay

3.2 Age of onset, progression, severity

  • In the rolandic epilepsy spectrum, seizures are typically childhood-onset and EEG features often activate in drowsiness/sleep, consistent with classic centrotemporal-spike epilepsies (review-level). (rudolf2009fromrolandicepilepsy pages 1-2)
  • SRPX2 phenotypes range from epilepsy with structurally normal MRI in some reports to epilepsy with perisylvian PMG in others, consistent with a “boundary” phenotype spanning functional and malformative presentations. (rudolf2009fromrolandicepilepsy pages 1-2, salmi2013tubacinpreventsneuronal pages 1-2)

3.3 Quality-of-life impact

Direct QoL instrument data (EQ-5D/SF-36/PROMIS) were not identified in retrieved evidence; however, the clinical features (speech dyspraxia, epilepsy, PMG) are expected to significantly impact communication and daily functioning. (Evidence gap)

4. Genetic / molecular information

4.1 Causal gene

  • SRPX2 (sushi repeat containing protein X-linked 2; OMIM 300642). (roll2010molecularnetworksimplicated pages 1-2)

4.2 Pathogenic variants (from retrieved evidence)

  • SRPX2 p.N327S — reported with rolandic epilepsy and verbal dyspraxia; causality questioned due to co-inheritance of another missense variant in most affected members. (salmi2013tubacinpreventsneuronal pages 2-2)
  • SRPX2 p.Y72S — associated with bilateral perisylvian polymicrogyria; discussed near an evolutionarily interesting residue R75K in structural modeling of a sushi domain. (royer2007molecularevolutionof pages 2-3)

Variant types in evidence: missense variants. (salmi2013tubacinpreventsneuronal pages 2-2)

Population allele frequencies / ClinVar classifications: not available in retrieved context. (Evidence gap)

4.3 Functional consequences

Rodent model evidence supports a loss-of-normal-developmental-function interpretation: * “Wild-type, but not the mutant human SRPX2 proteins, rescued the neuronal migration phenotype caused by Srpx2 silencing in utero” and increased alpha-tubulin acetylation. (salmi2013tubacinpreventsneuronal pages 1-2)

4.4 Modifier genes / epigenetics

Not established for SRPX2 in retrieved context. * A 2024 X-linked epilepsy review emphasizes that “epigenetic regulation and X-chromosome inactivation” can complicate X-linked genotype–phenotype correlations generally, which is relevant to interpreting female carriers, but is not SRPX2-specific evidence in the extracted lines. (bernardo2024xlinkedepilepsiesa pages 22-23)

5. Environmental information

No SRPX2-specific environmental, lifestyle, toxin, or infectious contributors were identified in the retrieved texts. (Evidence gap)

6. Mechanism / pathophysiology

6.1 Current mechanistic concepts

Two complementary mechanistic frames emerge from the retrieved evidence:

A) FOXP2 → SRPX2/uPAR transcriptional network (speech-related gene regulation)

  • The 2010 Human Molecular Genetics study provides experimental evidence that FOXP2 represses SRPX2 and uPAR and links this to speech-related disorders and epilepsy/malformation contexts. It reports that FOXP2 transfection reduced SRPX2 transcripts by 43.6% and uPAR transcripts by 38.6%, and inhibited SRPX2 and uPAR promoter activity by ~80.2% and 77.5%, respectively. (roll2010molecularnetworksimplicated pages 1-2)
  • Mechanistic variants in FOXP2 demonstrate disruption of this repression:
  • FOXP2 p.R553H abolishes regulation/binding (roll2010molecularnetworksimplicated pages 5-7)
  • FOXP2 p.M406T shows significant loss of SRPX2 promoter repression and altered intracellular localization (roll2010molecularnetworksimplicated pages 5-7, roll2010molecularnetworksimplicated pages 7-9)

Suggested GO biological process terms (mechanism mapping suggestions): * GO:0006355 regulation of transcription, DNA-templated * GO:0007399 nervous system development

B) Neuronal migration defects and tubulin acetylation (developmental epilepsy mechanism)

The 2013 Brain study provides a causal chain in a developmental rodent model: 1) Trigger: in utero Srpx2 knockdown 2) Upstream cellular process: abnormal neuronal migration during cortical development 3) Biochemical link: altered alpha-tubulin acetylation (wild-type SRPX2 increases acetylation; mutant does not rescue) (salmi2013tubacinpreventsneuronal pages 1-2) 4) Downstream electrophysiology:spontaneous epileptiform activity” recorded postnatally (salmi2013tubacinpreventsneuronal pages 1-2) 5) Pharmacologic prevention in utero:The neuronal migration defects and the post-natal epileptic consequences were prevented early in embryos by maternal administration of tubulin deacetylase inhibitor tubacin.” (salmi2013tubacinpreventsneuronal pages 1-2)

Suggested GO terms: * GO:0001764 neuron migration * GO:0000226 microtubule cytoskeleton organization

Suggested cell types (CL term suggestions): * CL:0000540 neuron * CL:0000127 cortical neuron (more specific mapping as appropriate)

6.2 Expert interpretation (authoritative-source synthesis)

A 2024 review of X-linked epilepsies frames SRPX2 as a gene initially linked to rolandic seizures and language/oromotor phenotypes and places it among key X-linked PMG genes, supporting the view that SRPX2 sits at a boundary between functional epilepsy-aphasia phenotypes and structural migration/cortical organization disorders. (bernardo2024xlinkedepilepsiesa pages 19-21)

7. Anatomical structures affected

7.1 Organ/system level

  • Central nervous system, especially speech-related cortical regions in the rolandic/perisylvian areas (review-level and mechanistic framing). (rudolf2009fromrolandicepilepsy pages 1-2, salmi2013tubacinpreventsneuronal pages 1-2)

7.2 Tissue/cell level

  • Developing cerebral cortex with involvement of neuronal migration processes (rat in utero model). (salmi2013tubacinpreventsneuronal pages 1-2)

Suggested UBERON terms (mapping suggestions): * UBERON:0000955 brain * UBERON:0001870 cerebral cortex * UBERON:0002771 frontal lobe operculum / perisylvian cortex (depending on ontology granularity)

8. Temporal development

  • The rolandic epilepsy spectrum is described as childhood-onset with centrotemporal EEG features often activated by sleep/drowsiness (review-level). (rudolf2009fromrolandicepilepsy pages 1-2)
  • The developmental mechanism is prenatal/early developmental: Srpx2 perturbation in utero produces migration defects with later postnatal epileptiform activity in the animal model. (salmi2013tubacinpreventsneuronal pages 1-2)

9. Inheritance and population

9.1 Inheritance

  • SRPX2-related rolandic epilepsy–speech dyspraxia has been described as X-linked (RESDX) in review-level evidence. (rudolf2009fromrolandicepilepsy pages 1-2)
  • A 2024 review notes SRPX2-associated PMG phenotypes have been observed to affect males, with the implication that skewed X-inactivation can modulate female phenotypes. (bernardo2024xlinkedepilepsiesa pages 19-21)

9.2 Epidemiology

No robust SRPX2-specific prevalence/incidence estimates were identified in the retrieved texts.

A relevant background statistic from a 2024 review (X-linked PMG, not SRPX2-specific): epilepsy is observed in approximately 80% of X-linked PMG cases. (bernardo2024xlinkedepilepsiesa pages 19-21)

10. Diagnostics

10.1 Clinical evaluation (real-world implementation)

SRPX2-related phenotypes lie at the intersection of epilepsy-aphasia spectrum and malformations of cortical development, suggesting a practical diagnostic approach: * EEG to identify centrotemporal spikes / focal epileptiform patterns in rolandic epilepsy presentations (review-level). (rudolf2009fromrolandicepilepsy pages 1-2) * Brain MRI to evaluate for bilateral perisylvian polymicrogyria and related cortical malformations where clinically indicated. The SRPX2 disease concept explicitly includes cases “with or without structural developmental alteration of the speech cortex.” (salmi2013tubacinpreventsneuronal pages 1-2)

10.2 Genetic testing

A PMG review recommends exploring genetic testing and notes challenges including de novo variants, mosaicism, and CNVs in PMG broadly; it explicitly includes SRPX2 in a suggested malformations-of-cortical-development gene panel. (james2022thegeneticlandscape pages 7-8)

In practice (inference consistent with review statements), SRPX2 evaluation is typically performed via: * NGS epilepsy and/or malformations-of-cortical-development panels including SRPX2 (james2022thegeneticlandscape pages 7-8) * WES/WGS when phenotype is broader or when panel testing is negative (review-level general recommendation in PMG). (james2022thegeneticlandscape pages 7-8)

10.3 Differential diagnosis (high-level)

Not systematically enumerated in retrieved context; however, SRPX2 sits within the set of genes implicated in PMG and epilepsy-aphasia spectrum. The 2024 X-linked epilepsy review highlights multiple X-linked PMG genes and emerging genes; SRPX2 is discussed among these. (bernardo2024xlinkedepilepsiesa pages 19-21)

11. Outcome / prognosis

SRPX2-specific long-term outcomes, mortality, and validated prognostic factors were not identified in the retrieved context.

Based on syndrome descriptions, disability burden is primarily driven by seizure control, degree of speech/oromotor impairment, and presence/extent of cortical malformation and intellectual disability (review-level). (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21)

12. Treatment

12.1 Current standard clinical management (real-world)

No SRPX2-specific controlled treatment studies were identified in retrieved texts.

For polymicrogyria broadly, a 2022 review summarizes real-world management as symptomatic: * “The first-line treatment for those with seizures is anti-seizure medications.” (james2022thegeneticlandscape pages 7-8) * Surgical candidacy may depend on lesion laterality/extent: unilateral focal PMG may be considered for resective surgery; bilateral PMG is generally not a good candidate for resection (review-level). (james2022thegeneticlandscape pages 7-8) * Supportive therapies: “Occupational therapy, physiotherapy, and speech therapy may help” some affected individuals. (james2022thegeneticlandscape pages 7-8)

Suggested MAXO terms (mapping suggestions): * MAXO:0000016 antiepileptic drug therapy * MAXO:0000757 speech therapy * MAXO:0000445 occupational therapy

12.2 Experimental / preclinical therapeutics

A key preclinical development is the 2013 Brain study showing in utero prevention of downstream epileptiform activity in a rodent model: * “The neuronal migration defects and the post-natal epileptic consequences were prevented… by maternal administration of tubulin deacetylase inhibitor tubacin.” (salmi2013tubacinpreventsneuronal pages 1-2)

This is not a current human therapy, but it provides mechanistic support for targeting microtubule/tubulin acetylation pathways in SRPX2-related developmental epilepsy mechanisms.

13. Prevention

No established primary prevention exists beyond genetic counseling for families.

For PMG broadly, the 2022 review highlights the importance of genetic testing and counseling and notes that risk assessment depends on inheritance and the identified cause. (james2022thegeneticlandscape pages 7-8)

14. Other species / natural disease

No naturally occurring SRPX2-related disease in other species was identified in the retrieved context.

15. Model organisms

A mechanistically informative rat in utero gene-silencing model exists: * Srpx2 silencing in utero produces neuronal migration defects and postnatal epileptiform activity, with rescue by wild-type human SRPX2 but not mutant SRPX2; tubacin prevents defects and epileptiform outcomes. (salmi2013tubacinpreventsneuronal pages 1-2)

2023–2024 “latest research” highlights (within retrieved evidence)

  • 2024 (International Journal of Molecular Sciences; published Apr 2024; DOI: 10.3390/ijms25074110): SRPX2 highlighted among principal X-linked PMG genes and linked to rolandic seizures, ID, speech delay, and orofacial dyspraxia. Provides review-level consolidation of SRPX2 positioning in X-linked PMG/epilepsy gene landscape. (bernardo2024xlinkedepilepsiesa pages 19-21)
  • 2023 (International Journal of Developmental Neuroscience; published Aug 2023; DOI: 10.1002/jdn.10290): broader context review on X-linked neuronal migration disorders, emphasizing limited epidemiologic data for neuronal migration disorders and the contribution of cortical malformations to refractory epilepsy. (edey2023x‐linkedneuronalmigration pages 5-6)

Limitation: No 2023–2024 primary SRPX2 case series or variant reclassification papers were successfully retrieved in the current tool run; therefore, recent patient counts, novel variants, and modern ACMG/ClinVar interpretations are not included here.

Structured summary table

Topic Summary Publication / year PMID / identifier(s) URL Citation
Disease names / synonyms / identifiers Evidence supports the SRPX2-associated disease spectrum including Rolandic epilepsy–speech dyspraxia / RESDX / rolandic epilepsy-speech dyspraxia syndrome and bilateral perisylvian polymicrogyria (BPP) / congenital bilateral perisylvian syndrome. OMIM numbers explicitly mentioned for SRPX2 (OMIM 300642), Rolandic epilepsy–speech dyspraxia (OMIM 300643), and bilateral perisylvian polymicrogyria (OMIM 300388). Open Targets context lists MONDO_0015587 rolandic epilepsy-speech dyspraxia syndrome and Orphanet 163721 Rolandic epilepsy - speech dyspraxia. Hum Mol Genet 2010; Open Targets context; IJMS review 2024 PMID not shown in context for 2010 paper; MONDO_0015587; Orphanet 163721; OMIM 300642/300643/300388 https://doi.org/10.1093/hmg/ddq415 (roll2010molecularnetworksimplicated pages 1-2, OpenTargets Search: -SRPX2, bernardo2024xlinkedepilepsiesa pages 19-21)
Inheritance Reported as an X-linked syndrome for SRPX2-related RESDX; females may show milder or variable manifestations, plausibly influenced by skewed X-inactivation. PMG literature notes familial PMG can be autosomal dominant, autosomal recessive, or X-linked, but the SRPX2 disorder specifically is X-linked in the cited syndrome reports. Epilepsia 2009; IJMS review 2024; PMG review 2022 PMID not shown in context https://doi.org/10.1111/j.1528-1167.2009.02214.x ; https://doi.org/10.3390/ijms25074110 ; https://doi.org/10.4103/aian.aian_97_22 (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21, james2022thegeneticlandscape pages 7-8)
Core phenotype: speech / oromotor Recurrent phenotypes across reports/reviews include speech delay, verbal/oral dyspraxia, oro-facial dyspraxia, and language-cortex dysfunction. These features are central to the named syndrome and often accompany epilepsy; intellectual disability may be variable. Epilepsia 2009; IJMS review 2024 PMID not shown in context https://doi.org/10.1111/j.1528-1167.2009.02214.x ; https://doi.org/10.3390/ijms25074110 (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21)
Core phenotype: epilepsy Seizures are typically rolandic/centrotemporal in the classic syndrome. Reviews connect SRPX2 to focal epilepsies of the rolandic/sylvian speech areas. In X-linked PMG broadly, epilepsy is observed in ~80% of cases. Epilepsia 2009; IJMS review 2024 PMID not shown in context https://doi.org/10.1111/j.1528-1167.2009.02214.x ; https://doi.org/10.3390/ijms25074110 (rudolf2009fromrolandicepilepsy pages 1-2, bernardo2024xlinkedepilepsiesa pages 19-21)
Core phenotype: cortical malformation SRPX2 is also linked to bilateral perisylvian polymicrogyria, a developmental malformation of the speech cortex; reviews note SRPX2 among the principal X-linked PMG genes. BMC Genet 2007; IJMS review 2024; PMG review 2022 PMID not shown in context https://doi.org/10.1186/1471-2156-8-72 ; https://doi.org/10.3390/ijms25074110 ; https://doi.org/10.4103/aian.aian_97_22 (royer2007molecularevolutionof pages 2-3, bernardo2024xlinkedepilepsiesa pages 19-21, james2022thegeneticlandscape pages 7-8)
Key SRPX2 variants Two historically emphasized missense variants are p.N327S (reported with rolandic epilepsy and verbal dyspraxia) and p.Y72S (reported with bilateral perisylvian polymicrogyria / rolandic seizures). The 2013 Brain study notes that the direct causal role of p.N327S has been questioned because of co-inheritance of another missense variant in most affected members. Brain 2013; BMC Genet 2007 PMID not shown in context https://doi.org/10.1093/brain/awt161 ; https://doi.org/10.1186/1471-2156-8-72 (salmi2013tubacinpreventsneuronal pages 2-2, royer2007molecularevolutionof pages 2-3, salmi2013tubacinpreventsneuronal pages 1-2)
FOXP2 network variants (mechanistic context) FOXP2 p.R553H abolishes repression/binding effects on SRPX2/uPAR regulatory sites; FOXP2 p.M406T causes partial loss of nuclear localization and significant loss of SRPX2 promoter repression. These FOXP2 variants are mechanistic network findings rather than primary SRPX2 disease alleles. Hum Mol Genet 2010 PMID not shown in context https://doi.org/10.1093/hmg/ddq415 (roll2010molecularnetworksimplicated pages 7-9, roll2010molecularnetworksimplicated pages 5-7, roll2010molecularnetworksimplicated pages 1-2)
Mechanism: FOXP2 represses SRPX2/uPAR FOXP2 directly down-regulates SRPX2 and uPAR; reported quantitative effects include 43.6% reduction of SRPX2 transcripts, 38.6% reduction of uPAR transcripts, and inhibition of SRPX2 and uPAR promoter activity by about 80.2% and 77.5%, respectively. This supports a FOXP2→SRPX2/uPAR speech-disorder network. Hum Mol Genet 2010 PMID not shown in context https://doi.org/10.1093/hmg/ddq415 (roll2010molecularnetworksimplicated pages 1-2)
Mechanism: neuronal migration / tubulin acetylation In utero Srpx2 silencing in rat cortex causes neuronal migration defects and later spontaneous epileptiform activity. Wild-type, but not mutant, human SRPX2 rescues the migration phenotype and increases alpha-tubulin acetylation, linking SRPX2 dysfunction to cortical development. Brain 2013 PMID not shown in context https://doi.org/10.1093/brain/awt161 (salmi2013tubacinpreventsneuronal pages 1-2)
Mechanism / experimental rescue Maternal treatment with the tubulin deacetylase inhibitor tubacin prevented both the migration abnormalities and postnatal epileptiform consequences in the rat model, providing proof-of-principle for pathway-targeted rescue in a developmental model. This remains preclinical, not a human standard of care. Brain 2013 PMID not shown in context https://doi.org/10.1093/brain/awt161 (salmi2013tubacinpreventsneuronal pages 1-2, salmi2013tubacinpreventsneuronal pages 2-2)
Recent review perspective (2023–2024) Recent reviews continue to place SRPX2 among important X-linked PMG and X-linked epilepsy genes. The 2024 review states SRPX2 was initially related to Rolandic seizures, ID, speech delay, oro-facial dyspraxia, and abnormalities in brain speech areas; the 2023 review discusses X-linked neuronal migration disorders and emphasizes limited epidemiologic data overall. Int J Mol Sci 2024; Int J Dev Neurosci 2023 PMID not shown in context https://doi.org/10.3390/ijms25074110 ; https://doi.org/10.1002/jdn.10290 (bernardo2024xlinkedepilepsiesa pages 19-21, edey2023x‐linkedneuronalmigration pages 5-6)

Table: This table condenses the main disease names, identifiers, inheritance, phenotypes, variants, mechanisms, and key quantitative findings for the SRPX2-related speech-epilepsy-polymicrogyria spectrum. It is designed as a quick reference for integrating evidence from primary and recent review sources.

References (URLs in-text)

Primary and review sources used in this report are those retrieved in the current run and cited by context ID throughout (pqac-...). Key URLs include: * Roll et al., Human Molecular Genetics (Dec 2010): https://doi.org/10.1093/hmg/ddq415 (roll2010molecularnetworksimplicated pages 1-2) * Salmi et al., Brain (Aug 2013): https://doi.org/10.1093/brain/awt161 (salmi2013tubacinpreventsneuronal pages 1-2) * Bernardo et al., Int J Mol Sci (Apr 2024): https://doi.org/10.3390/ijms25074110 (bernardo2024xlinkedepilepsiesa pages 19-21) * James et al., Ann Indian Acad Neurol (Jul–Aug 2022): https://doi.org/10.4103/aian.aian_97_22 (james2022thegeneticlandscape pages 7-8) * Rudolf et al., Epilepsia (Aug 2009): https://doi.org/10.1111/j.1528-1167.2009.02214.x (rudolf2009fromrolandicepilepsy pages 1-2) * OpenTargets SRPX2 associations (accessed via tool): (OpenTargets Search: -SRPX2)

References

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  2. (roll2010molecularnetworksimplicated pages 1-2): Patrice Roll, Sonja C. Vernes, Nadine Bruneau, Jennifer Cillario, Magali Ponsole-Lenfant, Annick Massacrier, Gabrielle Rudolf, Manal Khalife, Edouard Hirsch, Simon E. Fisher, and Pierre Szepetowski. Molecular networks implicated in speech-related disorders: foxp2 regulates the srpx2/upar complex. Human molecular genetics, 19 24:4848-60, Dec 2010. URL: https://doi.org/10.1093/hmg/ddq415, doi:10.1093/hmg/ddq415. This article has 132 citations and is from a domain leading peer-reviewed journal.

  3. (salmi2013tubacinpreventsneuronal pages 1-2): Manal Salmi, Nadine Bruneau, Jennifer Cillario, Natalia Lozovaya, Annick Massacrier, Emmanuelle Buhler, Robin Cloarec, Timur Tsintsadze, Françoise Watrin, Vera Tsintsadze, Céline Zimmer, Claude Villard, Daniel Lafitte, Carlos Cardoso, Lan Bao, Gaetan Lesca, Gabrielle Rudolf, Françoise Muscatelli, Vanessa Pauly, Ilgam Khalilov, Pascale Durbec, Yehezkel Ben-Ari, Nail Burnashev, Alfonso Represa, and Pierre Szepetowski. Tubacin prevents neuronal migration defects and epileptic activity caused by rat srpx2 silencing in utero. Brain : a journal of neurology, 136 Pt 8:2457-73, Aug 2013. URL: https://doi.org/10.1093/brain/awt161, doi:10.1093/brain/awt161. This article has 66 citations.

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  6. (royer2007molecularevolutionof pages 2-3): Barbara Royer, Dinesh C Soares, Paul N Barlow, Ronald E Bontrop, Patrice Roll, Andrée Robaglia-Schlupp, Antoine Blancher, Anthony Levasseur, Pierre Cau, Pierre Pontarotti, and Pierre Szepetowski. Molecular evolution of the human srpx2 gene that causes brain disorders of the rolandic and sylvian speech areas. BMC Genetics, 8:72-72, Oct 2007. URL: https://doi.org/10.1186/1471-2156-8-72, doi:10.1186/1471-2156-8-72. This article has 36 citations.

  7. (salmi2013tubacinpreventsneuronal pages 2-2): Manal Salmi, Nadine Bruneau, Jennifer Cillario, Natalia Lozovaya, Annick Massacrier, Emmanuelle Buhler, Robin Cloarec, Timur Tsintsadze, Françoise Watrin, Vera Tsintsadze, Céline Zimmer, Claude Villard, Daniel Lafitte, Carlos Cardoso, Lan Bao, Gaetan Lesca, Gabrielle Rudolf, Françoise Muscatelli, Vanessa Pauly, Ilgam Khalilov, Pascale Durbec, Yehezkel Ben-Ari, Nail Burnashev, Alfonso Represa, and Pierre Szepetowski. Tubacin prevents neuronal migration defects and epileptic activity caused by rat srpx2 silencing in utero. Brain : a journal of neurology, 136 Pt 8:2457-73, Aug 2013. URL: https://doi.org/10.1093/brain/awt161, doi:10.1093/brain/awt161. This article has 66 citations.

  8. (bernardo2024xlinkedepilepsiesa pages 22-23): Pia Bernardo, Claudia Cuccurullo, Marica Rubino, Gabriella De Vita, Gaetano Terrone, Leonilda Bilo, and Antonietta Coppola. X-linked epilepsies: a narrative review. International Journal of Molecular Sciences, 25:4110, Apr 2024. URL: https://doi.org/10.3390/ijms25074110, doi:10.3390/ijms25074110. This article has 14 citations.

  9. (roll2010molecularnetworksimplicated pages 5-7): Patrice Roll, Sonja C. Vernes, Nadine Bruneau, Jennifer Cillario, Magali Ponsole-Lenfant, Annick Massacrier, Gabrielle Rudolf, Manal Khalife, Edouard Hirsch, Simon E. Fisher, and Pierre Szepetowski. Molecular networks implicated in speech-related disorders: foxp2 regulates the srpx2/upar complex. Human molecular genetics, 19 24:4848-60, Dec 2010. URL: https://doi.org/10.1093/hmg/ddq415, doi:10.1093/hmg/ddq415. This article has 132 citations and is from a domain leading peer-reviewed journal.

  10. (roll2010molecularnetworksimplicated pages 7-9): Patrice Roll, Sonja C. Vernes, Nadine Bruneau, Jennifer Cillario, Magali Ponsole-Lenfant, Annick Massacrier, Gabrielle Rudolf, Manal Khalife, Edouard Hirsch, Simon E. Fisher, and Pierre Szepetowski. Molecular networks implicated in speech-related disorders: foxp2 regulates the srpx2/upar complex. Human molecular genetics, 19 24:4848-60, Dec 2010. URL: https://doi.org/10.1093/hmg/ddq415, doi:10.1093/hmg/ddq415. This article has 132 citations and is from a domain leading peer-reviewed journal.

  11. (james2022thegeneticlandscape pages 7-8): Jesmy James, Mary Iype, Mithran Omana Surendran, Ayyappan Anitha, and Sanjeev V. Thomas. The genetic landscape of polymicrogyria. Jul 2022. URL: https://doi.org/10.4103/aian.aian_97_22, doi:10.4103/aian.aian_97_22. This article has 14 citations and is from a peer-reviewed journal.

  12. (edey2023x‐linkedneuronalmigration pages 5-6): Juliet Edey, Payam Soleimani‐Nouri, Amelia Dawson‐Kavanagh, Muhamad Saad Imran Azeem, and Vasso Episkopou. X‐linked neuronal migration disorders: gender differences and insights for genetic screening. International Journal of Developmental Neuroscience, 83:581-599, Aug 2023. URL: https://doi.org/10.1002/jdn.10290, doi:10.1002/jdn.10290. This article has 10 citations and is from a peer-reviewed journal.

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