The melanocortin receptor genes are linked to and associated with the risk of polycystic ovary syndrome in Italian families

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder occurring in women of reproductive age. The disease is caused by a complex interplay of genetic and environmental factors including genes encoding components of the hypothalamic-pituitary-adrenal (HPA) axis. We have recently reported the association of melanocortin receptor genes (MC1R, MC2R, MC3R, MC4R, and MC5R) with the risk of type 2 diabetes (T2D) and/or major depressive disorder (MDD). The latter 2 disorders are comorbid with PCOS. In this study, we used microarray to test 12 single nucleotide polymorphisms (SNPs) in the MC1R gene, 10 SNPs in the MC2R gene, 5 SNPs in the MC3R gene, 6 SNPs in the MC4R gene, and 4 SNPs in the MC5R gene in 212 original Italian families with PCOS. We identified 1 SNP in MC1R, 1 SNP in MC2R, 2 SNPs in MC3R, and 2 SNPs in MC5R significantly linked and/or associated to/with the risk of PCOS in Italian families. This is the first study to report the novel implication of melanocortin receptor genes (MC1R, MC2R, and MC5R) in PCOS. MC3R and MC4R were previously reported in PCOS. However, functional studies are needed to validate these results.