Family-based analysis of the adiponectin gene polymorphisms and polycystic ovary syndrome

Abstract

To study the association between three single nucleotide polymorphisms (SNP; rs2241766, rs1501299 and rs12495941) variants of the adiponectin gene (ADIPOQ) and polycystic ovary syndrome (PCOS) in PCOS family trios. A total of 224 unrelated PCOS probands, their biological parents were recruited. Anthropometric variables such as waist circumference (WC), hip circumference (HC), height and weight were measured in all subjects during the first visit to the outpatient department. Body mass index (BMI) and waist- hip ratio (WHR) were calculated. Serum fasting glucose (FBG), fasting insulin (FINS), total cholesterol (TC), triglycerides (TG), low- density lipoprotein and highdensity lipoprotein cholesterol (HDL) levels were measured. PCOS patients were divided into two groups based on BMI: group A (BMI<25 kg/m²) and group B (BMI ≥ 25 kg/m²). Parents of PCOS patients were accordingly categorized into group C, D (fathers) and group E, F (mothers). The transmission disequilibrium test (TDT) was used to analyze the association between three SNP of ADIPOQ and PCOS. (1) A significant positive association was detected between SNP rs1501299 and PCOS (χ² = 7.093, P = 0.008). However we failed to find significant overtransmission of the other two SNP rs2241766 and rs12495941 from parents to PCOS offsprings (χ² = 1.620, P = 0.203; χ² = 0.713, P = 0.398). (2) Linkage disequilibrium (LD) was analyzed in the subjects, rs1501299 and rs2241766 were in weak LD (r² = 0.063, D' = 0.621). (3) The levels of WC, HC, WHR, testosterone, TG, HDL and FINS were significantly differences between obese and lean PCOS patients (P < 0.05). While in fathers we only found WC, HC, TC levels being statistically different (P < 0.05). Mothers of obese PCOS patients had increased levels of FINS compared with mothers of lean PCOS patients (P < 0.05). The genotype frequencies of the three SNP were not different in obese and lean PCOS patients and their parents (P>0.05). TDT confirms that SNP rs1501299 in the ADIPOQ is significantly associated with the risk of PCOS in the Chinese Han population. The three SNP of the ADIPOQ were not associated with the obesity of PCOS.