Nevertheless, effects of some SNPs appear to be more pronounced in children and diminish later in life as has been shown for the associations of variants in TMEM18, GNDPA2, MC4R, NEGR1, BDNF and KTCD15 with early-onset obesity [57], and particularly for INSIG2 variants [58–60]. Here, MC4R is linked to obesity due to melanocortin 4 receptor deficiency.