FTO and obesity due to melanocortin 4 receptor deficiency: Kanders et al. demonstrated breastfeeding moderating action in the association between FTO rs9939609 polymorphism (defined as an obesity-related polymorphism because of its role in increasing BMI and adiposity [128,129]) and children’s BMI [130], as also reported by Wu YY et al., whose research demonstrated that five months of exclusive breastfeeding attenuated the increase in BMI and delayed the timing of the adiposity peak among FTO rs9939609 variant carriers [131].