Type I Thanatophoric Dysplasia: Clinical Outcome in the Absence of Molecular Genetic Confirmation: A Case Report.

Thanatophoric dysplasia (TD) is the most common lethal congenital skeletal dysplasia, characterized by severe micromelia, a narrow thorax, and frontal bossing due to activating mutations in the fibroblast growth factor receptor 3 (FGFR3) gene on chromosome 4p16.3. First described by Maroteaux and Lamy in 1967, it carries a near-uniform perinatal mortality from respiratory insufficiency. We present the case of a male newborn in whom the diagnosis of thanatophoric dysplasia was established during the antenatal period.