Rapid genotyping for hepatitis B virus by nested-PCR using type-specific primers and its clinical significance

Objective To genotype rapidly for HBV by nested-PCR using type-specific primers and investigate the distribution of HBV genotypes in Shandong Province.Methods HBV genotypes were determined by nested-PCR analysis in randomly selected 178 HBV DNA positive patients, including 53 of asymptomatic HBV carriers (ASC),87 of chronic active hepatitis (mild,moderate and severe) and 38 of liver cirrhosis in Shandong Province.In the first PCR the samples were amplified by outer primers,then the products of the first PCR were amplified by 6 inner primers in MixA and MixB respectively in the second PCR.Results Of the 178 patients 85 (47.8%) were genotype C,63 (35.4%) were genotype B, and 17 (16.8%) were mixed genotype B and C.There was a statistical significance for the distributions of genotype B between active liver diseases and ASC(P0.01).HBV-DNA copies,HBeAg positive rates and ALT levels were higher in genotype C than those in genotype B (P0.001 and P0.005,respectively).However,the anti-HBe titers were significantly higher in genotype B than those in genotype C (P0.005).Conclusion HBV genotype B, C and mixed B and C exist in Shandong Province,and genotype C is the major genotype.The nested-PCR using type-specific primers for HBV genotyping is proved to be sensitive and specific for rapid determination of genotypes of HBV,so it can be used in clinical diagnosis and epidemiological study for HBV genotypes.