eP326: Genome sequencing reveals BHLHA9 gene duplication as cause of multi-generational split-hand/foot malformation with long bone deficiency

Split-hand/foot malformation (SHFM) is a form of distal limb deficiency that affects the central rays of the hands and/or feet. The phenotypic variability exhibited in SHFM is considerable and occurs between families, within families, and even between the limbs of a single individual. The hand and/or foot findings in affected individuals may occur in isolation or with other anomalies. Split-hand/foot malformation with long bone deficiency (SHFLD) is a rare autosomal dominant form of SHFM associated with deficiency of the tibia or other long bones and characterized by variable expressivity and incomplete penetrance.