β Scribed by Chun, Kathy; Siegel-Bartelt, Jacqueline; Chitayat, David; Phillips, John; Ray, Peter N.
No coin nor oath required. For personal study only.
The Antley-Bixler syndrome (ABS) is a rare syndrome with synostosis of cranial sutures and elbow joints as minimal diagnostic criteria. The inheritance has been suggested to be autosomal recessive based on two families with sib recurrence with both sexes being affected, and two cases born to consanguineous parents. We report the first case of ABS associated with an apparent dominant de novo mutation in the fibroblast growth factor receptor 2 (FGFR2) gene. The patient was found to be heterozygous for a C-->G transversion at nucleotide 1064, which predicts a Ser351Cys amino acid substitution in the IgIII domain of FGFR2. Apart from the craniosynostosis and elbow ankylosis, our patient also presented with severe spinal dysraphism, the first report of such a finding in association with ABS. This suggests that FGFR2 is expressed as early as the fourth week of embryogenesis when somite formation occurs. We propose that the Antley-Bixler syndrome is an autosomal dominant condition with possible gonadal mosaicism. Alternatively, there may be two types of ABS: an autosomal dominant form and an autosomal recessive form. In light of our findings, FGFR mutations should be looked for in other craniosynostosis patients with elbow synostosis.
π SIMILAR VOLUMES
We describe a girl with physical anomalies, accelerated skeletal maturation, failure to thrive, and respiratory difficulties consistent with a diagnosis of Marshall-Smith syndrome (MSS). Chromosome analysis showed an inverted duplication of chromosome 2 [46,XX,inv dup(2)(q37q32) de novo] identified
Fig. . The radiocontrast study obtained via the umbilical opening demonstrates the deformed urinary bladder, vesicoureteroreflux, the posterior urethra with normal calibration, and the atresia in the anterior urethra with cystic dilation behind.
Fig. 1. Front (A) and profile (B) of the phenotypically normal individual with the FGFR3 Pro250Arg mutation.
Dominant mutations in three fibroblast growth factor receptor genes (FGFRs1-3) cause Crouzon, Jackson-Weiss, Pfeiffer, and Apert syndromes. In the present study, 50 Brazilian patients with these four syndromes (27 Apert, 17 Crouzon, 5 Pfeiffer, and 1 Jackson-Weiss patients) were screened for mutatio