Genetic predisposition scores (GPS), particularly consisting of leptin-related SNPs (GPSleptin), were robustly associated with baseline overweight/obesity in children who slept ≤8 h/day (P < 0.001), whereas the association was ablated in those who slept ≥10 h/day (P > 0.05). Here, LEP is linked to obesity due to melanocortin 4 receptor deficiency.