Distribution of HBV genotypes and mutations in basic core gene promoter, pre C/C region in infected family clustering members

Abstract

Objective To investigate the distribution of HBV genotypes and the mutations in basic core gene promoter(BCP),pre C/C region in clustering family patients infected with chronic hepatitis B(CHB),and to discuss the related clinical significance.Methods A total of 98 CHB patients from 38 family with family clustering features were included in the experimental group,and 110 CHB patients without family clustering features were taken as controls.HBV genotypes were detected in CHB patients by nested PCR with genotype-specific primers.The mutations in BCP and pre C/C region were detected using PCR.Serum ALT,TBIL,ALB,HBV-DNA levels,and hepatitis B antigen and antibody were all examined.Results HBV genotype C was the predominant genotype(52.9%,36/68) in group of parents and their children,and genotype B was the predominant genotype in group of other infected family members(73.3%,22/30) and control group(67.3%,74/110);the frequency of HBV genotype C in group of parents and their children was significantly higher than other infected family members and control group(P0.01).There were only a few B+C and B+D mixed types.On the whole,HBV genotypes from the same family were basically the same.The frequency of BCP A1762T/G1764A mutations in clustering family CHB patients with genotype C(61.9%,26/42) was significantly higher than that in CHB patients with genotype C without family clustering features(35.7%,10/28)(P0.05),so was the HBV-DNA level(P0.01).Conclusion HBV genotype in clustering family is probably associated with the transmission route of virus.HBV genotype C may be easier to transmit from parents to their children.Genotype C and BCP A1762T/G1764A mutations may be associated with the development of CHB in clustering family.