Determine genotypes of the hepatitis B virus using restriction fragment lenght polymorphism(RFLP)

2. ABSTRACT Hepatitis B is one of the most common infectious diseases in the world. It has teen estimated that 350 million people world-wide are chronic hepatitis B virus (HBV) carriers. Hepatitis B virus (HBV) has been classified into 8 genotypes (A~H) based on an intergroup divergence of 8% or more in the complete nucleotide. Different genotypes of the hepatitis B virus may influence the clinical outcome of the disease. The Hepatitis B virus genotyping method using restriction fragment length polymorphism (RFLP) can reliably identify genotypes. HBV genotyping with the S gene sequence is consistent with genetic analysis using the foil genomic sequence. The aim of this study was to determine genotypes of the Hepatitis B virus using restriction fragment length polymorphism (RFLP) in the region of Elazig. A total of 127 HBV DNA positive patients were included in this study. Semi-nested PCR was performed to amplify a spesific part of S gene of HBV. Then, the PCR products were used for RFLP assay. After alignment of the S sequences, genotype specific regions are identified and digested by the restriction enzymes, Alwl, Earl, Hphl, Neil, and NlaN. The RFLP assay indicated that genotype D was the only detected type found in 127 samples. In conclusion, genotype D is the predominant type among hepatitis B patients in our region. This simple and easy HBV genotyping system using RFLP is considered to be useful for research on genotyping of HBV. Key Words: Hepatitis B virus, PCR, RFLP, genotypes of HBV.