ABSTRACT
BACKGROUND: Genetic variations in Human leukocyte antigen C (HLA-C), Zinc ribbon domain containing 1 (ZNRD1) and its antisense RNA (ZNRD1-AS1) genes are known to influence the HIV-1 replication and disease progression. OBJECTIVE AND METHOD: We evaluated the distribution of HLA-C (rs10484554, rs9264942) and ZNRD1 (rs8321) and ZNRD1-AS1 (rs3869068), single nucleotide polymorphisms (SNPs) in 266 HIV-1-infected and 223 unexposed-uninfected individuals from Northeast Brazil and their relation to HIV-1 infection, CD4 T cells count and viral load pre-treatment. RESULTS: HLA-C SNPs were in Linkage Disequilibrium (D'=0.84), constituting four possible haplotypes. Our results showed that HLA-C, ZNRD1 and ZNRD1-AS1 SNPs as well as HLA-C haplotypes frequencies were not significantly different between HIV-1-infected and unexposed-uninfected individuals. In addition, we analyzed HLA-C and ZNRD-1 and ZNRD1-AS1 SNPs considering CD4+ T cell counts and viral load before the antiretroviral treatment. Individuals carrying HLA-C rs9264942 TT genotype showed a significant increased level of HIV-1 viral load pre-treatment, in comparison with individuals carrying the CC genotype (p-value = 0.0092). Finally, we stratified our findings according to CCR5Δ32 allele presence along with the studied SNPs: no statistically significant influence over viral load pre-treatment has been found. CONCLUSION: The association between HLA-C rs9264942 SNP and viral load prior treatment in an admixed population from North East Brazil was in agreement with findings from previous studies obtained on different ethnic groups; however more studies should be conducted in order to clarify how HLA-C impair the HIV-1 replication.
Subject(s)
DNA-Binding Proteins/genetics , HIV Infections/genetics , HIV Infections/virology , HLA-C Antigens/genetics , Histocompatibility Antigens Class I/genetics , Polymorphism, Single Nucleotide , Viral Load , Adolescent , Adult , Brazil , CD4 Lymphocyte Count , Female , HIV-1/isolation & purification , Humans , Male , Middle Aged , Young AdultABSTRACT
BACKGROUND: HIV-1 virus is known to infect the host mainly through CD4+ T-lymphocyte cells, by interactions among the viral envelope proteins, CD4 receptor and HIV-1 coreceptors, such as chemokines receptors. Variations in the genes encoding HIV-1 coreceptors and their natural ligands have been shown to modify HIV-1 infection susceptibility and disease progression. METHODS AND RESULTS: We analysed the distribution of SNPs in chemokines (CCL3, CCL4, CCL5, CXCL12) and chemokine receptor (CXCR6) genes, in 268 HIV-1 infected patients (HIV-1+) and 221 healthy controls from Northeast Brazil, and their possible connection with susceptibility to HIV-1 infection. The genotyping were performed through allele specific fluorogenic probes using real time PCR. We observed that the T alleles and AT genotype of rs1719153 CCL4 SNP were more frequent in healthy controls (19.8% and 35.0%, respectively) than in HIV-1+ patients (T allele: 14.1%; OR=0.67; 95%CI=0.47-0.95; p-value=0.020; and AT genotype: 24.4%; OR=0.61; 95%CI=0.40- 0.93; p-value=0.021) after correcting for age and sex. The rs1719134 (CCL3) and rs1719153 (CCL4) SNPs presented linkage disequilibrium (D'=0.83). The AT haplotype frequency was increased in healthy controls (17.3%) in relation to HIV-1+ patients (11.0%; OR=0.62; 95%CI=0.42-0.93; p-value=0.020). CONCLUSION: Since our results revealed an increased frequency of alleles and genotypes of CCL3/CCL4 SNPs and haplotype (CCL3-CCL4) among healthy controls, we suggest that these variations might have a potential protective role against HIV-1 infection.