The aryl hydrocarbon receptor (AhR)-repressor (AhRR) is the regulator of AhR signaling pathway, which plays an important role in metabolism of xenobiotics such as dioxin and reactive oxygen species (ROS). The aim of the present study is the investigation of the AhRR-c.565C>G transversion polymorphism the fertile and infertile and to compare the TAC levels of seminal plasma of these groups according to the genotype frequences. Semen and blood samples were collected from the Fatemezahra IVF centre (Babol, Iran) and analysed on the basis of World Health Organization (WHO) guidelines. Using general boiling DNA extraction methods, DNA fragments of exon 6 were amplified using AhRR-F/AhRR-R primers. Analysis of direct sequencing of polymerase chain reaction (PCR) products confirmed AhRR-c.565C>G transversion mutation in exon6 in infertile mens. TAC levels of seminal were measured by TBAR methods. The results showed that the TAC level of semen plasma in GG genotype was significantly higher than CC group (p<0.05) whereas, there was no significant difference between fertile and infertile heterozygous. So it is likely that the G allele (alanin allele) has a role in increasing of antioxidant capacity of seminal plasma. The function of the C allele (prolin allele) reflects the advers effects on male infertility. Based on these finding and on the role of AhRR gene in AhR signaling pathway, it is suggested that the transversion mutation in exon 6 of the AhRR gene can be used as a marker for idiopatic men in subsequent studies.
