HBV Genotyping Based On Directly S HBV DNA Gene Sequencing Analysis And Its Clinical Application

Objective: To establish a method of HBV genotyping by directly gene sequencing of HBV DNA S gene and to discuss the relationship between the HBV genotype and clinical status.Methods: With PCR to amplify HBV DNA S genes ,HBV genotype can be identified by compared directly HBV DNA S gene sequencing with Genebank standard sequence A-H. HBV S gene sequencing analysis were conducted in 165 chronic asymptomatic HBV carriers(ASC) and acute hepatitis B (AH),chronic hepatitis B (CHB),liver cirrhosis (LC) and severe hepatitis (SH).In order to verify this method stability and specificity, 20 serums were randomly chosen from 165 serums to repeat the HBV DNA S gene sequencing.Results: The repeat experiment showed that the genotyping result of the same HBV isolate was identical. Among 165 serums 20 were genotype (12.1%) ,143 were genotype C (86.7%) ,1 was genotype D (0.6%) and 1 was mixed B and C (0.6%) .The percentage of genotypes B and C in ASC. AH, CHB, LC and SH patients were significantly different(X2= 11.27, P<0.01). Compare with genotype B, genotype C was more common found in CHB patients (69.2% vs 45%, X2=4.61 ,P<0.05) ,but in LC patients no difference was found. HBeAg positive rate in patients with genotype C was higher than with genotypes B (63.6% vs 35 % , X2=6.00 ,P<0.05), HBeAb positive rate in patients with genotype C was lower than that with genotypes B (X2=7.16,P<0.01) .Conclusions: 1. HBV DNA S gene directly sequencing analysis for genotyping simplified the traditional gene sequence genotyping method ,at same...