Mutations of S protein gene in positive HBsAg and anti-HBs patients with chronic hepatitis B virus infection / 中华临床感染病杂志

ABSTRACT

Objective To investigate mutations of S protein gene in positive HBsAg and anti-HBs patients with chronic hepatitis B virus (HBV) infection.Methods Fifteen HBsAg(+) and anti-HBs(+) patients and 22 HBsAg(+) and anti-HBs (-) patients (control group) admitted in Renmin Hospital of Wuhan University during January and December 2011 were enrolled in the study.The S protein gene was amplified and sequenced, and the amino acid sequences were translated from the obtained DNA sequences and compared with the reference sequences.Results Compared with the control group, HBsAg (+) and anti-HBs(+) patients showed a higher variability in amino acid within major hydrophilic region (2.95 vs.0.78,x2 =18.059, P＜0.01) and the a determinant (4.44 vs.1.52, x2 =6.985, P＜0.01).The mutations in a determinant at positions P127T, G130E, G130N, M133S, F134I, T140I and G145R were detected only in HBsAg(+) and anti-HBs (+) patients.Conclusion Co-existence of HBsAg and anti-HBs in patients with chronic HBV infection might be associated with the increased amino acid mutations in and around the a determinant of protein S.