Perinatal imaging findings and molecular genetic analysis of thanatophoric dysplasia type 1 in a fetus with a c.2419T>G (p.Ter807Gly) (X807G) mutation in FGFR3.
The diagnosis of thanatophoric dysplasia type 1 was suspected clinically, and FGFR3 sequencing showed a c.742_743insTGT variant, which predicts p.R248delinsLC.
A recently described cystic renal dysplasia in a patient with thanatophoric dysplasia type 1 due to a germ line FGFR3 mutation might portend to an involvement of mutational FGFR3 activation in renal cyst formation, but this speculation needs further evaluation.
Exon 7 of the FGFR3 gene was analyzed in 10 prenatal samples with type 1 TD, as well as in 30 control individuals for the presence of the c.742 C > T variant using melting curve analysis with a high-resolution melting instrument.
We report on a case of thanatophoric dysplasia type 1 (TD1) due to a Tyr373Cys mutation in the fibroblast growth factor receptor 3 (FGFR3) gene with soft tissue syndactyly of the fingers and toes.
Japanese cases of type 1 thanatophoric dysplasia exclusively carry a C to T transition at nucleotide 742 of the fibroblast growth factor receptor 3 gene.