Relation Between IL-6Polymorphism And Susceptibility To Chronic Hepatitis B Virus Infection

Aim To identify the relationship between the four tag single nucleotide polymorphisms(tagSNPs) of interleukin-6(IL-6) gene and genetic susceptibility to chronic hepatitis Bvirus (HBV) infection in the Han Chinese population.Methods We collected boold samples of Chinese patients with chronic HBV as casegroup and collected patients with self-limiting HBV-infected individuals as control group.All of patients were treated in the infectious department of the first and second affiliatedhospital of Anhui medical university from December2011to September2012. GenomicDNA was isolated from whole blood of all the subjects, using phenol/chloroform withMaXtract high-density tubes. Tag SNPs(tagSNPs) were identified using genotype datafrom the panel (Han Chinese in Beijing) of the phase II HapMap Project.The MultiplexSnapshot technique is used for genotyping Four tagSNPs in IL-6(rs17147230, rs2066992,rs2069837, rs2069852). The genotype, allele frequencies, Haplotype frequencies andLinkage Disequilibrium (LD) were calculated and analyzed.Results (1) Five haplotypes were involved in the analysis, which frequencies werehigher than0.03. One of the haplotypes, TTAA, is significantly different between twogroups. Overall haplotype P values were: ATAA, P=0.605, odds rate(OR)[95%confidence interval(CI)]=1.056(0.860-1.297); TGAG, P=0.385, OR(95%CI)=1.179(0.813-1.709); TGGG, P=0.549, OR(95%CI)=1.087(0.827-1.429); TTAA, P=0.004,OR(95%CI)=0.655(0.491-0.873); TTAG, P=0.266, OR(95%CI)=1.272(0.832-1.944). (2) The genotype frequencies of case samples for AA, AT and TT of rs17147230were30.94%,48.10%,20.96%, and which of control samples for AA, AT and TT ofrs17147230were28.24%,51.50%,20.27%. The genotype frequencies for GG, GT andTT of rs2066992were8.98%,37.92%,53.09%in case samples, and6.64%,39.20%,54.15%in control samples. The genotype frequencies of case samples for AA, AG andGG of rs2069837were66.07%,30.14%,3.79%and which of control samples were67.11%,28.57%,4.32%. The genotype frequencies of case sample for AA, AG and GGof rs2069852were41.52%,45.71%,12.77%，and those of control samples for AA, AGand GG is45.85%,43.85%,10.30%. No statistically significant difference betweencases and controls (rs17147230, P=0.625; rs2066992, P=0.500; rs2069837, P=0.853;rs2069852, P=0.380).3) The allele frequencies of case samples for A, T of rs17147230were54.99%,45.01%,and53.99%,46.01%in control samples. The allele frequencies for G, T of rs2066992were27.94%,72.06%in case samples,26.25%,73.75%in control samples. The allelefrequencies of case samples for A, G of rs2069837were81.14%,18.86%and which ofcontrol samples for A, G of rs2069837were81.40%,18.60%. The allele frequencies ofcase sample for A, G of rs2069852were64.37%,35.63%and which of control sampleswere67.77%,32.23%. No statistically significant difference between cases and controls.rs17147230，P=0.6959，OR(95%CI)=1.0413(0.8500-1.2756)； rs2066992，P=0.4598，OR(95%CI)=1.0898(0.8676-1.3689)； rs2069837， P=0.8982，OR(95%CI)=0.9832(0.7587-1.2742); rs2069852, P=0.165, OR(95%CI)=0.859(0.693-1.064).Conclusion The four tagSNPs of IL-6gene may be associated with susceptibility tochronic HBV infection in the Han Chinese population.