KMT2D and colonic neoplasm: Hu et al. (2013), Guo et al. (2013) and Lee et al. (2013) showed reduced global H3K4me1 levels in a KMT2C/D (MLL3/4) double-knockout colon cancer cell line, and identified a majority of KMT2D binding sites located in putative enhancer elements. Kmt2d is essential for mouse adipogenesis, myogenesis, macrophage activation and lymphomagenesis, demonstrating additional roles for KMT2D as a mono- and di-methyltransferase at enhancers (Lee et al., 2013; Kaikkonen et al., 2013; Ortega-Molina et al., 2015).