Abstract: Objective：To explore the association of the single nucleotide polymorphism (SNP) rs3802457 of C9orf3 gene with polycystic ovarian syndrome (PCOS). Methods: 106 women with PCOS (the PCOS group) and 41 healthy females(as the control) were recruited in the first affiliated hospital of Guangzhou Medical University. Genomic DNA was extracted from the EDTA anticoagulants whole blood, and the target C9orf3 gene was amplified by PCR and sequenced by Sanger reactions. The biochemical data of the blood fat and clinical variables were compared between the PCOS group and the control group. Results: There were three kinds of genotypes, including CC, CT and TT in the rs3802457 of the C9orf3 gene. The genotype frequencies of rs3802457 were 87.7%, 12.3% and 0% in the group of PCOS. Comparably, they were 68.3%, 29.3% and 2.4% in the control group. The allele frequencies of C and T were 93.9% and 6.1% in the PCOS group, and 82.9% and 17.1% in the control group, respectively. There were significant differences in the genotype frequencies (P＜0.05) and the allele frequencies (P＜0.05) in the rs3802457 of the C9orf3 gene between the two groups. Body mass index and waist-to-hip in the PCOS group were significantly higher than those in the control group (P＜0.05). No significant differences in the data of biochemistry (total cholesterol /high density lipoprotein /low density lipoprotein) were observed between the two groups (P＞0.05) except for triglyceride (P＜0.05). The HDL level in those PCOS patients with CC genotype was significantly lower than that in PCOS patients with CT genotype (P＜0.05). Conclusions: SNP variant of rs3802457 of C9orf3 gene may be involved in the pathogenesis of the PCOS.

Key words: Polycystic ovary syndrome, Polymorphism, genetic, C9orf3 gene, Genetic predisposition to disease