Background: The rs368234815 polymorphism of interferon-λ4 (IFN-λ4) gene (IFNL4) is involved in HBV surface antigen (HBsAg) clearance in non-uremic subjects. The rs368234815 ΔG/ΔG genotype can express IFN-λ4 while the TT/TT genotype cannot. We investigated whether rs368234815 is associated with the development of HBsAg antibodies (anti-HBs) in response to vaccination or infection, and HBsAg loss after infection in uremic patients on extracorporeal dialysis.Research design and methods: Dialyzed patients (n = 467) were genotyped for rs368234815 by the polymerase chain reaction-restriction fragment length polymorphism method. Non-responders to HBV vaccination we compared with responders. HBsAg positive patients not able to develop anti-HBs we compared with individuals who eliminated HBsAg and generated anti-HBs. HBsAg positive patients we compared with subjects who eliminated HBsAg.Results: The ∆G allele was associated with the 1.6-fold higher risk not to develop anti-HBs titers ≥10 IU/L in response to HBV vaccination and infection (P = 0.016 adjusted for gender, age at dialysis onset, HCV RNA). The ∆G/∆G genotype indicated a higher probability of non-responsiveness to HBV vaccination than the TT/TT genotype (OR 2.64, 95%CI 1.01-6.87, adjusted P = 0.048).Conclusions: In extracorporeal dialysis patients, IFNL4 rs368234815 is associated with the capacity to produce protective anti-HBs titers in response to HBV vaccination.
Keywords: Extracorporeal dialysis; gene polymorphism; hepatitis B virus; infection; interferon; vaccination.