FTO and obesity due to melanocortin 4 receptor deficiency: As well, previous research has shown that breastfeeding can influence the key genes in the obesity pathway, decreasing the expression level of fat mass and obesity‐associated (FTO) and carnitine palmitoyltransferase IA (CPT1A) genes while increasing the expression level of the PPAR‐α gene in 5–6 month old infants (Cheshmeh et al., 2020).