Genome-wide DNA methylation quantitative trait locus (mQTL) analysis of human pancreatic islets has revealed 383 significant CpG sites in known diabetes loci as potential methylation targets; importantly, some of the identified candidate genes, i.e., glutathione peroxidase 7 (GPX7), glutathione S-transferase theta 1 (GSTT1), and sorting nexin 19 (SNX19) directly affect key biological processes such as proliferation and apoptosis of pancreatic islet beta cells [20]. The gene discussed is GPX7; the disease is diabetes mellitus.