Holt-Oram Syndrome, also known as hos, is related to interatrial communication and atrioventricular block. An important gene associated with Holt-Oram Syndrome is TBX5 (T-Box Transcription Factor 5), and among its related pathways/superpathways are Nervous system development and Cardiac conduction. Affiliated tissues include heart and bone, and related phenotypes are joint stiffness and split hand