BackgroundPolycystic ovary syndrome (PCOS) is the most common endocrinopathy in women. This study was designed to investigate the associations of vitamin D receptor (VDR) gene variants with PCOS risk and the severity of the disease phenotype among Egyptian women.MethodsIn this study, 185 women with PCOS and 207 fertile women as controls were recruited. Cases were divided into phenotype groups based on their clinical and paraclinical features. Clinical and laboratory data were measured in the patient and control groups. All individuals were genotyped for nine single-nucleotide polymorphisms (SNPs) located across the VDR gene using TaqManallelic discrimination real-time polymerase chain reaction.ResultsWomen with PCOS were significantly (P≤ 0.001) higher body mass index (BMI) (22.77 ± 2.5) than controls (21.68 ± 1.85 kg/m2). Women with PCOS had significantly higher anti-Mullerian hormone, prolactin, luteinizing hormone (LH), LH/follicle-stimulating hormone (FSH), free testosterone, total testosterone, and dehydroepiandrosterone sulfate levels than the control group (P≤ 0.001). The level of FSH was significantly lower in women with PCOS than in the control group (P≤ 0.001). Analysis of the VDR rs4516035, rs2107301, rs1544410 (BsmI), and rs731236 (TaqI) SNPs showed a significant association with PCOS phenotype A. Furthermore, rs2228570 (FokI), rs3782905, rs7975232 (ApaI), and rs739837 SNPs showed a significant association with PCOS phenotype C. Furthermore, rs11568820 SNP showed a significant association with PCOS phenotype D (P< 0.05).ConclusionsThe findings of this study indicate that variations in the VDR gene were associated with an increased risk of PCOS in Egyptian women.