Indeed, genetic defects in the H3K36 trimethyltransferase gene SETD2 (25, 26, 27) impair the MMR function (22), and histone mutations that disrupt H3K36me3’s interaction with SETD2 or MutSα result in MMR deficiency (22, 23, 28). The gene discussed is SETD2; the disease is mismatch repair cancer syndrome 1.