Thanatophoric Dysplasia Type 2 phenotype curation notes for issue #1458
Date: 2026-04-19
Curator: Codex
Scope: Phenotype section only for kb/disorders/Thanatophoric_Dysplasia_Type_2.yaml
Curation approach
- Prefer primary human clinical sources with subtype-specific TD2 wording when available.
- Keep frequency only when the cited abstract directly supports it.
- Remove mechanistic or prevalence claims from phenotype descriptions when the phenotype evidence was only associative.
- Avoid adding isolated anomalies from single case reports unless they are clinically important or already central to TD2 recognition.
Phenotype evidence added or strengthened
PMID:3130852- Supports
Cloverleaf skullas very frequent in TD2: "Almost all type 2 cases have severe CS." PMID:11241532- Supports TD2 prenatal findings: narrow thoracic cage, hydrocephalus, cloverleaf skull, straight short femora, and polyhydramnios.
- Supports
Redundant skin foldsfrom 3D ultrasound wording in the same TD series. PMID:23323754- Supports
Pulmonary hypoplasiaas a constant morphologic finding in thanatophoric dysplasia. - Supports
Temporal lobe dysplasiaas a recurring neuropathologic finding in a 25-case autopsy series. PMID:24075385- Supports subtype-specific TD2 facial and limb findings: macrocephaly, frontal bossing/prominent forehead, brachydactyly, narrow chest, straight femora, cloverleaf skull.
PMID:11965423- Confirms that the CNS malformation pattern also occurs in TD2, including temporal lobe polymicrogyria and hippocampal abnormalities.
PMID:33520059- Supports
Respiratory insufficiencyand its relationship to reduced thoracic capacity and hypoplastic lungs. PMID:23573386- Used cautiously for
Short ribsbecause the abstract explicitly lists short ribs among core TD features while also distinguishing TD2 by straight femurs and severe cloverleaf deformity.
Unsupported or softened points
- Removed unsupported frequency qualifiers from most phenotypes; retained a frequency only for
Cloverleaf skull. - Softened
Hydrocephalusfrom a generalized/common claim to a documented prenatal finding in some TD2 fetuses. - Softened
Small foramen magnumto avoid overstating TD2-specific evidence from broader FGFR3 chondrodysplasia literature. - Simplified survivor phenotypes (
Global developmental delay,Short stature,Acanthosis nigricans) to stay close to the cohort data without extra mechanistic inference. - Left out one-off anomalies such as pseudoencephalocele, encephalocele, cleft palate, holoprosencephaly, and vascular anomalies because they appear too case-specific for the core phenotype section.