Previous systematic reviews [8, 9] have reported differentially methylated loci in genes in T2DM blood cells including ABCG1, TXNIP, KCNQ1. While another such review by Muka et al. reported several epigenetically regulated genes from blood cells, adipose tissue, muscle and placenta, there was no overlap between them, and no association was found between global DNA methylation and T2DM/hyperglycemic markers [10]. The gene discussed is ABCG1; the disease is type 2 diabetes mellitus.