Family association study between tumour necrosis factor a gene polymorphisms and polycystic ovary syndrome in Han Chinese

Polycystic ovary syndrome (PCOS) is a complex disease involving genetic and environmental components. Tumour necrosis factor a (TNFa) is a proinflammatory cytokine in the pathogenesis of PCOS. The genetic association between polymorphisms of TNFa gene and PCOS was investigated. A family based study was conducted with 216 family trios (648 participants) having a proband with PCOS. Transmission disequilibrium test (TDT) was used to analyse the association between two single nucleotide polymorphisms (SNP) (rs1799964, rs1799724) of TNFa gene and PCOS. Minor allele frequencies of the SNP were 0.178 (rs1799964) and 0.118 (rs1799724). The two SNP were in Hardy-Weinberg equilibrium; TDT was only conducted when one parent was heterozygous. Of 216 trios, 112 trios of rs1799964 and 76 trios of rs1799724 were tested. A significant difference in transmission was found for rs1799964 (transmitted: non-transmitted = 73 : 39; χ2 = 10.321; P = 0.0013). rs1799724 showed no evidence of an association with PCOS; risk alleles were over transmitted (transmitted: non-transmitted = 43 : 33; χ2 = 1.316). Transmission disequilibrium of the two SNP indicated that rs1799964 may participate in the pathogenesis of PCOS in Chinese women. These data provide a basis for further studies of TNFa in the cause of PCOS.