Hepatitis B virus Genotypes in West Azarbayjan Province, Northwest Iran.

BACKGROUND: Infections caused by Hepatitis B are one of the world health's most serious problems. According to assessments, nearly 500,000 to 1.2 million people die each year due to chronic hepatitis, cirrhosis of the liver and hepatocellular carcinoma. Hepatitis B is one of the diseases which can be transferred through blood and its products. Clinical importance of genotypes of hepatitis B virus and their relations with mutations are well known.

AIM: Since epidemiological data resulting from determining genotypes and sub-genotypes of hepatitis B can help a lot in defining a vaccination plan, antiretroviral therapy, detection and prevention of diseases, genotypes of this virus in hepatitis B patients were evaluated in West Azarbaijan province.

MATERIALS AND METHODS: In this cross-sectional study, serum samples of 100 hepatitis B patients (70 male/30 female) were taken randomly from Urmia University of Medical Sciences (UMSU) referrals, Urmia, Iran; and were tested positive for the presence of surface antigens of hepatitis B virus (HBsAg) using ELISA method. In the first method, after extracting the DNA of the virus, sequencing of S genes was carried out using Sanger method, and the sequences were aligned and edited using Bioedit software. In the next step, phylogenic analysis of the sequences was done in comparison with the reference sequences which were extracted from a gene bank, utilising Neighbour-joining assay method with CLUSTRAL W software. To ensure genotyping accuracy, the samples were tested once more, using Nested PCR method.

RESULTS: The results were consistent with the sequence method and the dominant genotype in patients suffering hepatitis was type D. In other words, Iranian's HBV genotypic types are homogeneous and in close coordination with each other.

CONCLUSIONS: The results reveal that D genotype is the main genotype of HBV in West Azarbayjan province, northwest Iran. Presence of this genotype was in conformity conformed withto the low rate of acute liver diseases caused by hepatitis B chronic infection, cirrhosis of the liver and hepatocellular carcinoma.