The etiology of ED-syndactyly syndrome 1 (EDSS1; OMIM#613573) has been attributed to genetic variations within the poliovirus receptor related 4 (PVRL4) gene, which has been more recently designated as NECTIN4 located on chromosome 1q23.1. The gene discussed is NECTIN4; the disease is Ectodermal dysplasia - syndactyly syndrome.