GPX1 and obesity due to melanocortin 4 receptor deficiency: GPX1 rs1800668 had an increased risk of obesity under homozygote comparison (G/G vs. A/A: OR = 2.65, 95%CI = 1.11–6.32, p = 0.048) and recessive models (G/G vs. A/A-A/G: OR = 2.63, 95%CI = 1.12–6.18, p = 0.024).