Epidemiology Study On Hepatitis B Virus Genotypes And Subgenotypes In Guangxi

OBJECTIVE TO investigate the epidemiological characteristics of hepatitis B virus genotypes and subgenotypes in GUANGXI.Providing suggestions for the prevention and control of Hepatitis B,and providing basic data for the research of Pathogenic mechanism and vaccine development in different genotype,also help confirm the high risk group with liver cancer and liver cirrhosis.METHODS This study was a descriptive epidemiologic study.Study members were HBV infected individuals,and were collected from five regions in Guangxi,include the east,south,west,north and middle region.Experimental method used a nested polymerase chain reaction(nPCR)assay for amplification of HBV DNA S gene.Sequence analysis of S gene for genotyping,and subgenotypes were determined by phylogenetic analysis.RESULTS In total,379 samples was amplified successfully,all of them were genotyped.54.35%(206/379)were genotype C,43.5%(165/379)were genotype B,2.11%(8/379)were genotype G,None of any other genotypes was found.And significant differences were observed in the distribution in different regions and age groups(P=0.000?0.009),but no significant differences were observed in different genders(P=0.152).371 samples were subgenotyped.Among the genotype B isolates,96.25%,3.75% were subgenotype B2,B4.And no significant differences were observed in different regions ? genders and age groups(P=0.073 ? 0.410 ? 0.671).Among the genotype C isolates,72.06%,25.49%,2.45% were subgenoype C1,C5,C2,and the distribution of subgenotpye C has a significant difference between different regions(P=0.00),but no significant differences were observed in different genders and age groups(P=0.491?0.220).HBV-DNA level has no significant differences in different genotypes(H=2.707,P=0.258)?subgenotypes(H=4.308,P=0.366).CONCLUSIONS Genotype C is predominant in GuangXi,followed by genotype B.Genotype C is dominant in the south?east and the middle regions and people aged 40 to 59 years old,while genotype B in the north and the west,and is predominant in people younger than 40 and elder than 60 years old.B2 and C1 are the main subgenotypes.The distribution of subgenotype C is affected by regional factors,C5 was dominant in the westh of Guangxi while C1 is in the other regions.