ABSTRACT
<p><b>OBJECTIVE</b>To understand full-length sequence of HBV isolated from high incidence hepatocellular carcinoma area-Longan county, Guangxi.</p><p><b>METHODS</b>The nested polymerase chain reaction (nPCR) was used for amplifying the whole HBV DNA in sera of asymptomatic carriers. The products were sequenced by clone sequencing and homological analysis.</p><p><b>RESULTS</b>This isolate contained 3 215 bases. The genotype was C and the serotype was adw. There were 40 point mutations in polymerase gene which made 11 amino acids change. There were 11,2 and 3 point mutations in PreS1, PreS2 and S gene respectively which made 3,1,1, amino acids change. Six point mutations including the double mutations (nt 1762 A to T, 1764 G to A) were found in X gene leading to 4 amino acids change. There were 13 point mutations in C gene which made 2 amino acids change. No mutation was found in a determinant and Pre C. The isolate was quite close to the isolate from Vietnamese in evolution while far from the genotype C isolates from Shanghai, Beijing and Tibet.</p><p><b>CONCLUSION</b>No special sequence was found in the isolate from high incidence hepatocellular carcinoma area, Longan county, Guangxi.</p>
Subject(s)
Adult , Humans , Male , Amino Acid Sequence , Base Sequence , Carcinoma, Hepatocellular , Epidemiology , Carrier State , Virology , China , Epidemiology , Genotype , Hepatitis B , Virology , Hepatitis B virus , Genetics , Incidence , Liver Neoplasms , Epidemiology , Molecular Sequence Data , Open Reading Frames , Genetics , Point Mutation , Sequence Analysis, DNA , Sequence HomologyABSTRACT
<p><b>OBJECTIVE</b>To understand the distribution of hepatitis B virus genotype in Guangxi and its clinical significance.</p><p><b>METHODS</b>Nested polymerase chain reaction (nPCR) was used for amplification of HBV DNA in sera of asymptomatic carrier (ASC) of hepatitis B virus (HBV) and patients with different liver diseases from southern and northern Guangxi. Specimens from 161 subjects were positive for HBV DNA and HBV genotype was determined by using restriction fragment length polymorphism analysis, direct sequencing or cloning sequencing.</p><p><b>RESULTS</b>The prevalence of genotype A was 3.7% in all samples and that of genotype B, C and D was 21.7%, 72.7% and 1.2%, respectively. No other genotypes (such as genotype E, F, G, H) were found. The prevalence of genotype C showed an increasing trend in ASC, chronic hepatitis, liver cirrhosis and hepatocellular carcinoma (HCC) group; in contrast, the prevalence of genotype B showed an opposite trend, although no statistically significant difference was observed, except between ASC and HCC (P=0.05). The HBeAg positive rate was higher, and the anti-HBe positive rate was lower in patients with chronic genotype C infection than in those with genotype B (P<0.05 for both). Liver function test (ALT) abnormality was more severe in genotype C group than in genotypes A and B groups having acute or chronic infection (P<0.01 for all comparisons). The prevalence of genotype C in southern Guangxi was higher than that in northern Guangxi. In contrast, the prevalence of genotype B in southern Guangxi was lower than that in northern Guangxi.</p><p><b>CONCLUSIONS</b>1. The predominant HBV genotypes in Guangxi were genotypes B and C. The major genotype in southern Guangxi was genotype C; while that in northern Guangxi was genotype B, which implied that the distribution of HBV genotype C was consistent with the incidence of HCC in Guangxi. 2. Genotype C maybe associated with development of severe liver diseases including HCC. 3. Genotype A,D and B+C were mostly found in acute, hepatitis and chronic hepatitis group.</p>