Oxytocin receptor (OXTR) is a risk gene for polycystic ovarian syndrome

Oxytocin (OXT) controls appetite, promotes diet-induced energy expenditure, and may protect against obesity. Furthermore, the oxytocin system controls ovarian follicle luteinization and steroidogenesis as well as adrenal steroidogenesis, which if impaired might lead to anovulation and hyperandrogenism, signs found in women with polycystic ovarian syndrome (PCOS). PCOS is a common complex endocrine disorder of reproductive-age women, and it often presents with impaired glucose metabolism, insulin resistance (IR), and type 2 diabetes (T2D). The oxytocin receptor gene (OXTR) may confer a risk for PCOS, conceivably through dysregulation of metabolism, ovarian follicle maturation, and ovarian and adrenal steroidogenesis. Therefore, we aimed to investigate whether OXTR variants confer risk for PCOS.

In 212 Italian subjects with T2D and PCOS, we have analyzed 22 single nucleotide polymorphisms (SNPs) within the OXTR gene for linkage to and/or linkage disequilibrium (LD, i.e., association) with PCOS. We tested whether the significant risk variants were independent or part of an LD block.

We found 5 independent variants significantly linked to/in LD with PCOS within the peninsular families.

This is the first study to report OXTR as a novel risk gene in PCOS. Functional and replication studies are needed to confirm these results.