A meta-analysis published in Lancet in 2021 consisting of 71 studies (including 2495 patients with PCOS and 2520 controls) revealed that non-obese PCOS patients have significantly higher circulating levels of Chemerin, Leptin, Resistin, and Visfatin but a significantly lower circulating level of Adiponectin when compared with non-obese healthy controls (6). This evidence concerns the gene RETN and polycystic ovary syndrome.