摘要
AIM: Traditional hepatitis B virus (HBV) genotyping methods using restriction fragment length polymorphism (RFLP) can reliably identify genotypes A to F. As HBV genotypes G and H have been recently identified, this study was to establish an accurate and simple genotyping method for all eight HBV genotypes (A to H).METHODS: Two hundred and forty HBV small S sequences obtained from GeneBank were analysed for restriction enzyme sites that would be genotype-specific. Restriction patterns following digestion with restriction enzymes BsrⅠ, StyⅠ, DpnⅠ, HpaⅡ, and EaeⅠ, were determined to identify all eight HBV genotypes. Mixed genotype infections were confirmed by cloning and further RFLP analysis.RESULTS: The new genotyping method could identify HBV genotypes A to H. Genotypes B and C could be determined by a single step digestion with BsrI and StyI in parallel. This was particularly useful in the Far East where genotypes B and C are predominant. Serum samples from 187 Chinese HBV carders were analysed with this genotyping system, and the genotype distribution was 1.1% (2), 51.9% (97), 40.6% (76) and 4.8% (9) for genotypes A, B, C, and D, respectively. Mixed genotypes were found in only 3 patients (1.6%). Sequence data analysis confirmed the validity of this new method.CONCLUSION: This HBV genotyping system can identify all eight HBV genotypes. It is accurate and simple, and can be widely used for studies on HBV genotyping.
AIM:Traditional hepatitis B virus(HBV)genotyping methods using restriction fragment length polymorphism(RFLP)can reliably identify genotypes A to F.As HBV genotypes G and H have been recently identified,this study was to establish an accurate and simple genotyping method for all eight HBV genotypes(A to H). METHODS:Two hundred and forty HBV small S sequences obtained from GeneBank were analysed for restriction enzyme sites that would be genotype-specific.Restriction patterns following digestion with restriction enzymes BsrIⅠ StyⅠ,DpnⅠ,Hpa/Ⅱ,and EaeⅠ,were determined to identify all eight HBV genotypes.Mixed genotype infections were confirmed by cloning and further RFLP analysis. RESULTS:The new genotyping method could identify HBV genotypes A to H.Genotypes B and C could be determined by a single step digestion with BsrⅠ and StyⅠ in parallel.This was particularly useful in the Far East where genotypes B and C are predominant.Serum samples from 187 Chinese HBV carriers were analysed with this genotyping system,and the genotype distnbution was 1.1%(2),51.9%(97),40.6%(76)and 4.8% (9)for genotypes A,B,C,and D,respectively.Mixed genotypes were found in only 3 patients(1.6%).Sequence data analysis confirmed the validity of this new method. CONCLUSION:This HBV genotyping system can identify all eight HBV genotypes.It is accurate and simple,and can be widely used for studies on HBV genotyping.
基金
Supported by theMajor State Basic Research Development Program of China.973 Program,No.G1999054106
and the National Science Fund for Distinguished Young Scholars,No.30225042
