| Background: Hepatitis B virus(HBV)infection is the risk factors of human health, affects about 350 million persons worldwild. In china, there are about 93 million chronic carriers of HBV, including 20 million chronic hepatitis B patients. HBV infection can become chronic, leading to liver failure, liver cirrhosis, or cancer. HBV belongs to hepadnaviridea. Because its revertase lacks calibration function, nucleotide sequence easily occurs base pairing mistakes during reproduction, manifesting different genotypes. Now based on an intergronp divergence of 8% or more of the complete genomes, HBV can been classified into eight genotypes(A~H). And it is classified into different subgenotypes when the divergence is more than 4%, but lower than 8%. In recent years, the sudies found that HBV genotypes and subtypes have obvious geographic distribution characteristic. In my country mainland popular HBV genotype have four genes model of A,B,C,D. Genotype C is primary in the north area; in the south area, B genotype is the main one; D genotype was found in many areas. C genotype mainly has C1 and C2 subgenotype, C2 subtype is maily distributed in the north and the southeast area; B genotype maily has B2 subgenotype. The studies indicated that HBV genotype and subgenotypes maybe closely correlate with clinic manifestations, progression, treatment and prognosis of HBV correlated liver diseases. So studing HBV genotype and subgenotype distributiong of the area and the relationship with clinic has important significance.Objective: to study HBV genotype and subgenotype distribution, and analyze the relationship of HBV genotype or subgenotype and HBV correlated liver diseases, to guide clinic.Methods: 1.Serum samples of HBV infection patients were obtained in the Beijing Ditan hospital from Jun 2009 to Mar 2010,choicing 118 samples who didn't accept any treatment; deleting patients infected by other hepatitis virus, persons of liver damage by other causes, of immunity function enhancing or reducing, of glucose or renal function anomaly, and pregnancy. The selected patients were collected 10ml blood in vein, then -20℃preserved. Detecting ALT,AST,HBV DNA,HBeAg, and so on. 2.Designing primers by HBV A~D genotype all genome sequence of GenBank, amplified by the nested PCR(ntPCR), sequenced with direct sequencing method, constructing subtypes evolutionary tree by MEGA4. 3. Statisticing the data.Results: 1.Of 118 patients, genotypes C were found in 81(68.64%), D in 34(28.81%), and B in 3(2.54%); C1 and C2 subtypes were found in C genotype, D1 and D4 subtypes in D genotype, B1 and B4 subtype in B genotype, with C2(64.41%)and D4(27.97%)subtypes primarily. 2.Genotype C and subtype C2 in the hepatocellular carcinoma(HCC)group have higher rates(90.00%); D genotype and D4 subtype in the 1iver cirrhosis(LC)group have higher(30.00%)lever; B genotype only found in the CHB and LC groups; there was no statistically signifitions difference between CHB,LC,HF and HCC groups(P>0.05). 3. Average age lever, gender, HBeSAg positive rate, ALT and HBV DNA lever of genotype C were higher than genotype D, but there is still no obvirous statistical difference(P>0.05); above indexes in C2 subtype higher than D4 subtype, but also having no statistical significant(P>0.05).Conclution: 1. In these patients, C genotype was predomiant, follwed by D and B genotype, having no ather types. 2. The subgenotypes including C1,C2,D4,D1,B1,B4, and C2 is the most one. 3. The genotypes and subtypes in the CHB,LC, HF and HCC groups had no obvious difference. 3. Gender, age,serological and virusal indexs between C and D genotype, C2 and D4 subtype had no obvious difference. |
PDF Full Text Request