MYH6 and hypoplastic left heart syndrome: Dominant (14) and recessive (13) damaging variants in MYH6 have been related to poor ventricular function and need for cardiac transplantation in HLHS patients, and recessive damaging variants in MYH6 were associated with abnormal ventricular function in a study of a wide range of CHD (7), although no segregation of MYH6 variants has thus far been demonstrated.