Association of OX40L gene polymorphism with multiple sclerosis in Iranians

Abstract

IntroductionThe exact etiology of multiple sclerosis is unknown but recent studies indicated a link between tumor necrosis factor superfamily member 4 and the disease. Polymorphisms located in the regulatory region of the gene may affect its phenotype. Hence, we aimed to investigate the association of promoter polymorphisms of the gene with multiple sclerosis and also to estimate the frequency of haplotypes in the patients and healthy subjects. MethodsTwo hundred age- and sex-matched subjects including 100 patients and 100 healthy subjects were investigated in the study. Genotype and allele distributions of rs3850641, rs1234313, and rs10912580 polymorphisms in the promoter region of the gene were investigated by polymerase chain reaction-restriction fragment length polymorphism. In addition, haplotype frequencies estimation and linkage disequilibrium analysis were performed by SNPStats web tool. ResultsThe distribution of AA, AG and GG genotypes of rs3850641 was significantly different between the patient and healthy groups (P = 0.009). In addition, frequencies of A and G alleles of rs3850641 were different between the groups (P < 0.001). Also the distribution of rs3850641 genotypes was different between the women of the both groups (P = 0.007). Our analysis revealed that rs3850641 AG (Odds ratio = 0.393, 95 % confidence interval = 0.170–0.907, P = 0.029) and GG (Odds ratio = 0.373, 95 % confidence interval = 0.168–0.830, P = 0.016) genotypes were associated with decreased risk of the disease. However, rs1234313 genotype and allele distributions were not different between the groups. The distribution of rs10912580polymorphism. AA, AG, and GG genotypes was significantly different between the groups (P = 0.007). rs10912580 AG genotype was associated with low risk of the disease (Odds ratio = 0.252, 95 % confidence interval = 0.102–0.623, P = 0.003). The distribution of haplotypes was statistically different between the patient and healthy groups (P < 0.001). A-G-A was the most frequent haplotype among the patients and the estimated frequency was higher than that of the control group (0.5527 versus 0.3739). ConclusionThe distribution of rs3850641 and rs10912580 genotypes was different between the patients and healthy subjects. Moreover, rs3850641 AG and GG genotypes and also rs10912580 AG genotype were associated with low risk of the disease in Iranians. Further studies with large groups are recommended to show whether genotype variation in the patients could alter the response to treatment or not.