Lack of association between two genetic polymorphisms of SOD2 (rs2758339 and rs5746136) and the risk of opium dependency

Abstract

Abstract Introduction Superoxide dismutase-2 (EC 1.15.1.1; SOD2, OMIM: 147460) is a tetrameric enzyme which contains manganese in its active site. It is an important enzyme involved in the cellular detoxification by converting highly toxic superoxide radicals into less reactive molecules, hydrogen peroxide and oxygen. Several single nucleotide polymorphisms have been well defined in the gene encoding SOD2 , including the potentially functional polymorphisms of rs2758339 and rs5746136. Aim The aim of the present study is to investigate the associations between the rs2758339 (A/C substitution) and rs5746136 (A/G substitution) polymorphisms and the risk of dependency to opium. Material and methods The present case–control study was performed in Shiraz (southern Iran) on 143 opium dependent and 569 healthy controls. The genotypes of the rs2758339 and rs5746136 polymorphisms were determined by polymerase chain reaction. Results and discussion Statistical analysis showed that there was no significant association between the study polymorphisms and the risk of opium dependency. A significant linkage disequilibrium was observed between the study SOD2 polymorphisms. Statistical analysis showed that there was no significant association between the haplotypes of the polymorphisms and the risk of opium dependency. Conclusions The present data revealed that the rs2758339 and rs5746136 polymorphisms of SOD2 are not risk factors for dependency to opium.