Recent studies have found that patients with auriculocondylar syndrome have mutations in the genes, EDN1, EDNRA1, PLCB4 and GNAI3, which function in the endothelin signalling pathway42, 43, 44; however, mutations in HAND2 have not been identified in patients with auriculocondylar syndrome. This evidence concerns the gene HAND2 and auriculocondylar syndrome.