LEP and obstructive sleep apnea syndrome: ADIPOQ gene-Adiponectin, C1Q and Collagen Domain Containing, AHR-aryl hydrocarbon receptor, CIH-Chronic Intermittent Hypoxia, FADS1-fatty acid desaturase 1, FFA-free fatty acid, MRS-magnetic resonance spectroscopy, NAFLD-nonalcoholic fatty liver disease, NASH-non-alcoholic steatohepatitis; OSA-Obstructive Sleep Apnoea, PCOS-polycystic ovarian syndrome, LEP gene-leptin gene, TGF-B-transforming growth factor beta*rate-limiting enzymes for PUFA conversion and are recognized as main determinants of PUFA levels