MC4R and obesity due to melanocortin 4 receptor deficiency: DNA methylation also plays a promising role in regulation of obesity; this was demonstrated in a study involving administration of Lactobacillus rhamnosus and Bifidobacterium lactis to pregnant women, which resulted in a decrease in the methylation of the FTO and MC4R promoters in the women and their children (Vahamiko et al., 2019).