MC4R was selected since the associations between variants in this gene with obesity, T2D, and eating behavior have been widely studied (17, 18), and recently it has been reported to be differentially methylated in spermatozoa of lean subjects as compared to obese patients (35), as well as in vegans as compared to omnivores (34). Here, MC4R is linked to obesity due to melanocortin 4 receptor deficiency.