Moreover, genetic variants of the PRL locus (6p22.2 – p21.3) have been associated with alterations in body mass index in genome-wide association studies (18), and SNPs located near the PRLR gene correlate with an increased risk for gestational diabetes and obesity (19) strengthening the connection between prolactin and metabolic disorders. Here, PRL is linked to obesity due to melanocortin 4 receptor deficiency.