Association of Genetic Polymorphisms in TNF and MIF Gene with the Risk of Primary Dysmenorrhea

Abstract

Primary dysmenorrhea, which affects 90 % of adolescent girls and more than 50 % of menstruating women worldwide, is characterized by recurrent pain during menses in the absence of a detectable organic disease. The aim of this study is to assess the association between MIF −173 and TNF −308 genetic polymorphisms and the clinical features of primary dysmenorrhea. The study population comprised 154 unrelated female patients with clinical diagnosis of dysmenorrhea, and a total of 144 control subjects were recruited consecutively. The MIF −173G > C promoter polymorphism (rs755622) and TNF gene −308G > A (rs1800629) polymorphism were analyzed by polymerase chain reaction-based restriction fragment length polymorphism assay. Two fragments (268 and 97 bp) were seen when the G allele was present at position –173, and three fragments (206, 97, and 62 bp) were observed when the C allele was present. Two fragments (87 and 20 bp) were seen when G allele was present at position −308. There were statistically significant associations between age at menarche and history of back pain among dysmenorrhea patients and MIF gene −173G > C polymorphism (p = 0.003 and p = 0.042, respectively). The genotype and allele frequencies of −308G > A polymorphism showed statistically significant differences between dysmenorrhea patients and controls (p = 0.023 and p = 0.009, respectively). A high association was also observed when the patients were compared with the controls according to the GG genotype versus GA+AA genotypes (p = 0.009). The present study showed that the TNF-α −308 GG genotype may be a useful tool to predict the susceptibility of dysmenorrhea.