In human studies, investigations of blood samples from the Dutch Hunger Winter cohort at the age of 60 years, report an increased DNA methylation induced by periconceptional exposure to the famine in genes known to be involved in adipose tissue metabolism, specifically leptin and the fat mass and obesity associated gene (FTO) [116] suggesting a possible suppression of its activity. The gene discussed is LEP; the disease is obesity due to melanocortin 4 receptor deficiency.