Correlation of interleukin-6 RS1800796 gene polymorphism with enterovirus 71 infection

Abstract

Objective To explore the relationship between the interleukin-6(IL-6) RS1800796 gene polymorphism and susceptibility of Enterovirus 71(EV71) infection. Methods One hundred and twenty-three children with EV71 infection were selected as infection experimental group from March 2012 to December 2014 in the Central Hospital of Xiangtan, and they were divided into mild EV71 infection group (62 cases) and severe EV71 infection group (61 cases). And 52 age-and gender-matched healthy children were selected as the healthy control group.Two mL blood samples were collected from all subjects, and DNA was extracted by Beijing Optimal Boland Gene Technology LTD.The SNaPshot was used to determine the genotype for G/C polymorphism at RS1800796 position of IL-6 gene. Results The genotype frequency of IL-6 RS1800796 GG in the infection experimental group [73.2%(90/123 cases)]was significantly higher than that in the healthy control group[48.1%(25/52 cases)], and the difference was statistically significant(χ2=10.215, P=0.002, OR=2.945, 95%CI: 1.500-5.782). No significant difference was found in the distribution of genotype frequency of the IL-6 RS1800796 GG between the mild EV71 infection group and the severe EV71 infection group[71.0%(44/62 cases)vs.75.4%(46/61 cases), χ2=0.309, P=0.685]. The G allele in IL-6 RS1800796 G/C was more frequent in the infection group (85.0%)than that in the control group(70.2%), and the difference was statistically significant(χ2=10.183, P=0.002, OR=2.399, 95%CI: 1.389-4.143). No significant difference was found in allele frequency of the IL-6 RS1800796 G between the mild EV71 infection group and the severe EV71 infection group(83.1%vs.86.9%, χ2=0.703, P=0.477). Conclusion The G allele of IL-6 RS1800796 confers susceptibility to infection of EV71.But G allele carrier will not increase the risk of severity after infection. Key words: Hand-foot-and-mouth disease; Enterovirus 71; Interleukin-6; Single nucleotide polymorphism