This gene is a member of the basic helix-loop-helix family. The encoded protein is a transcription factor involved in limb development. Mutations in this gene have been associated with mesoaxial synostotic syndactyly Malik-Percin type (MSSD). Copy number variation of a locus containing this gene has been linked to a form of split-hand/foot malformation with long bone deficiency (SHFLD3). [provided by RefSeq, Mar 2015].