Association of HTLV-1 infection prevalence with TLR7 single nucleotide polymorphisms (rs179008 & rs179009) in asymptomatic blood donors in Khorasan Province of Iran

Abstract

BackgroundHuman T-lymphotropic virus type 1 (HTLV-1) cause two diseases in humans such as adult T-cell leukemia/lymphoma (ATL) and HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). About, 15–20 million persons are infected with HTLV-1 in worldwide. Single nucleotide polymorphisms (SNPs) are a genetic variation that occurs in >1% of the general population; they can alter promoter activities, gene expression, mRNA stability, and protein structure and function.Our aim in this study was to investigate the association between SNPs within Toll like receptor 7 (TLR7) (rs179008 and rs179009) and susceptibility to HTLV-1 infection among asymptomatic blood donors in Iran. MethodsA total of 100 asymptomatic HTLV-1 carriers and 118 healthy blood donors were studied. After extracting genomic DNA from all samples, amplification was performed using specific primers. Then, the restriction fragmentation length polymorphism (RFLP) method was used to evaluate the SNPs within TLR7. Data analysis was administered using SPSS version 22. ResultsThe frequency of the AA, AT, TT genotypes of TLR7 (rs178008) was 73%, 22%, and 5% in the patient group; while for those in the control group the values were 50%, 40.7%, and 9.3%, respectively. Moreover, the frequency of the TLR7 rs179008 A allele was 84% in the HTLV-1 patients group and 69.6 % in the control group. Also, the two groups were significantly different concerning the frequency distribution of the TLR7 (rs178008) genotypes and alleles (p = 0.001). ConclusionThere was a significant association between TLR7 (rs178008) SNP and HTLV-1 infection and the T allele of TLR7 (rs178008) SNP might be considered as a protective factor against HTLV-1 virus infection although additional evidence is needed.