A case of thanatophoric dysplasia with characteristic radiological, histological and molecular findings

Thanatophoric dysplasia (TD) is one the most common lethal skeletal with an incidence of in 20,000. It caused by de novo mutation fibroblast growth factor receptor 3 (FGFR3) which turn leads to reduced proliferation and maturation plate chondrocytes. Two subtypes have been described. Type I typically features short long bones bowed femurs, while type II manifests straighter femurs cloverleaf skull due craniosynostosis.1 Our case a 21 week gestation female baby diagnosed on 20 ultrasound. The postmortem survey showed characteristic TD, such as ribs ‘telephone receiver’ femurs. full examination crown-heel length 222mm (<5th centile, 237.4mm), relatively large head flattened nasal bridge. Bilateral humeri were there was bowing Deep fissures seen bilateral temporal lobes. Histologically, disorganisation retardation proliferating, hypertrophic calcified zones plate. post mortem findings highly suggestive TD I. Whole exome sequencing analysis FGFR3:c.742C>T diagnostic Reference 1. French T, Savarirayan R. Dysplasia. 2004 [updated 2020 Jun 18]. In: Adam MP, Everman DB, Mirzaa GM, Pagon RA, Wallace SE, Bean LJH, Gripp KW, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): University Washington, Seattle; 1993–2022. PMID: 20301540.