Frequencies of IL10 SNP genotypes by multiplex PCR-SSP and their association with viral load and CD4 counts in HIV-1-infected Thais.

Background: Interleukin (IL)-10 is an immuno-regulatory cytokine, levels of which can be influenced by single nucleotide polymorphisms (SNPs) in the promoter. Some, but not all previous studies have shown associations of IL10 SNPs with HIV-1 disease progression, using markers such as viral load or CD4 count. There are few data on IL10 SNP frequencies and HIV-1 disease in regions where non-B HIV-1 subtypes predominate. Objective: To determine genotypes, haplotypes, allele frequencies and associations with markers of HIV-1 disease progression of IL10 SNPs. Methods: A new multiplexed PCR-SSP assay to detect IL10 SNPs at positions -1082, -819 and -592 was developed and used to determine genotypes and haplotypes in 244 HIV-1 CRF01_AE-infected northern Thais having a median time since HIV-1 infection of 2.7 years. Results: At position -1082 of IL10 , AA genotype and A allele were the most common (87.3% and 93.2%, respectively). The -819 CT and -592 CA genotypes were the most prevalent (44.3%), and -819T and -592A were the most prevalent alleles (64.8%). The ATA/ATA was the most common genotype (42.6%) with the most prevalent haplotype of ATA (64.7%). No associations of any of the three IL10 SNPs with CD4+ or CD8+ T cell counts or with viral load were found. Conclusions: This first report of IL10 -1082A, -819T and the IL10 -592A allele frequencies in HIV-1-infected Thais shows the highest frequencies in HIV-1-infected persons worldwide. The lack of association of IL10 SNPs with CD4+ T cell count and viral load suggest that other genes may influence these markers in HIV-1-infected Thais.