EHMT2 (also known as G9a) and the highly homologous EHMT1 (also known as GLP) are HKMTs partly responsible for mono- and di-methylation of lysine nine of histone 3 (H3K9me1 and H3K9me2, respectively); repressive chromatin marks found on the promoter regions of genes that are often aberrantly silenced in cancer [17]. The gene discussed is EHMT2; the disease is cancer.