FADS1 and obesity due to melanocortin 4 receptor deficiency: The two genes, the brain-derived neurotrophic factor gene (BDNF) (rs7103411) and the fat mass and obesity-associated gene (FTO) (rs1558902), together with delta-5-desaturase (D5D) activity, 20:5n-3 in serum cholesteryl esters (CE), fasting blood glucose, abdominal skinfold thickness, apolipoprotein-B, and high-density lipoprotein cholesterol (HDL-C) at age 50, significantly predicted the risk of MetS at age 70.