Direct sequencing of NKX2-5 and HAND1 revealed a total of three heterozygous nonsynonymous sequence alterations, two in NKX2-5 and one in HAND1. Both NKX2-5 sequence alterations identified in patients of different cardiac disease phenotypes affected the alanine residue at position 119 and were passed on from an unaffected parent. This evidence concerns the gene HAND1 and heart disorder.