Relationship between polymorphisms near the IL28B gene and spontaneous HBsAg seroclearance: a systematic review and meta-analysis

Polymorphisms near the interleukin (IL) 28B gene have been proposed to be associated with spontaneous clearance of the hepatitis C virus. The purpose of this study was to assess the relationship between IL28B polymorphisms and the rate of spontaneous hepatitis B surface antigen (HBsAg) seroclearance by means of meta-analysis. MEDLINE/PubMed and EMBASE were utilized to identify relevant studies. Odds ratio (OR) and 95% confidence interval (CI) were analysed together to assess the strength of the association. Subgroup analyses were mainly performed according to ethnicity. A total of 4028 cases with persistent chronic hepatitis B and 2327 spontaneously recovered controls were included from 11 studies. The single nucleotide polymorphism (SNP), rs12979860, had no significant association with HBsAg seroclearance (OR = 0.98, 95% CI: 0.84-1.14 in the dominant model; OR = 1.00, 95% CI: 0.68-1.46 in the recessive model; and OR = 0.95, 95% CI: 0.82-1.09 in the allelic model). The SNP, rs12980275, had no significant association either (OR = 1.03, 95% CI: 0.84-1.26 in the dominant model; OR = 1.17, 95% CI: 0.46-2.96 in the recessive model; and OR = 1.04, 95% CI: 0.86-1.26 in the allelic model), nor did the SNP, rs8099917 (OR = 0.94, 95% CI: 0.77-1.15 in the dominant model; OR = 0.74, 95% CI: 0.34-1.62 in the recessive model; and OR = 0.93, 95% CI: 0.77-1.13 in the allelic model). Similarly, the results of subgroup analyses by ethnicity also showed no association in either the Asian group or non-Asian group. We concluded that there was no significant association between common IL28B polymorphisms and the rate of spontaneous HBsAg seroclearance.