In particular, mutations in the H3K4 methyltransferase KMT2D (also known as MLL2, MLL4 and ALR) have been identified as a major cause of Kabuki syndrome, with ∼60% of patients diagnosed with CHDs, most frequently aortic coarctation, atrial and ventricular septal defects. This evidence concerns the gene KMT2D and ventricular septal defect 1.