In adipose tissue of morbidly obese pre-diabetic patients, trimethylation of histone H3 at lysine 4 (H3K4me3), a gene activation mark, is found to be enriched at the promoters of genes associated with adipogenesis and lipid metabolism (e.g., LPL, SREBF2, SCD1, PPARG) (Castellano-Castillo et al., 2019), as well as at the E2F transcription factor 1 (E2F1), a contributor of obesity pathogenesis (Fajas et al., 2002; Haim et al., 2015; Denechaud et al., 2017). The gene discussed is E2F1; the disease is obesity due to melanocortin 4 receptor deficiency.