Open AccessExpanding the phenotype for the recurrent p.Ala391Glu variant in FGFR3 : Beyond crouzon syndrome and acanthosis nigricans
Author(s) -
Rymer Karen,
Shiang Rita,
Hsiung Anting,
Pandya Arti,
Bigdeli Tim,
Webb Bradley T.,
Rhodes Jennifer
Publication year - 2019
Publication title -
molecular genetics and genomic medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.765
H-Index - 29
ISSN - 2324-9269
DOI - 10.1002/mgg3.656
Subject(s) - craniosynostosis , exome sequencing , medicine , crouzon syndrome , proband , missense mutation , acanthosis nigricans , genetics , genetic heterogeneity , phenotype , dermatology , pathology , anatomy , biology , mutation , insulin resistance , obesity , gene
Background Craniosynostosis, or premature fusion of the skull sutures, is a group of disorders that can present in isolation (nonsyndromic) or be associated with other anomalies (syndromic). Delineation of syndromic craniosynostosis is confounded due to phenotypic overlap, variable expression as well as molecular heterogeneity. We report on an infant who presented at birth with multisuture synostosis, turribrachycephaly, midface hypoplasia, beaked nose, low set ears, a high palate and short squat appearing thumbs, and great toes without deviation. The additional MRI findings of choanal stenosis and a Chiari I malformation suggested a diagnosis of Pfeiffer syndrome. First tier molecular testing did not reveal a pathogenic variant. Methods Whole exome sequencing on DNA samples from the proband and her unaffected parents was utilized to delineate the variant causative for the Pfeiffer syndrome diagnosis. Results On whole exome sequencing, a de novo NM_000142.4:c.1428C>A missense variant causing a p.Ala391Glu amino acid change in FGFR3 has been identified. The p.Ala391Glu change has been predominantly identified in patients with Crouzon syndrome with acanthosis nigricans. Conclusions This finding illustrates the first reported case of a child with an overlap with Pfeiffer syndrome to have the p.Ala391Glu variant.