Temtamy Preaxial Brachydactyly Syndrome: A Case Report with Possible Phenotypic Expansion

Brachydactyly, caused by shortened or missing bones in the fingers or toes, can occur in isolation or as part of syndromes involving disruptions in BMP signaling. Temtamy preaxial brachydactyly syndrome (TPBS) is a rare autosomal recessive disorder characterized by symmetrical shortening of thumbs and big toes, facial dysmorphism, hearing loss, and developmental delays. We report a child from India with gross motor delay, recurrent knee dislocation, joint hypermobility, and characteristic finger and toe abnormalities. Radiology showed brachydactyly, short metacarpals, symphalangism, and extra ossification centers. Exome sequencing revealed a novel nonsense variant in CHSY1 (c.1231C>T; p.Gln411Ter). These findings expand the phenotypic spectrum of TPBS while acknowledging the possibility of an additional underlying diagnosis.