IDENTIFICATION AND GENOTYPING OF HEPATITIS B VIRUS BY PCR ASSAY USING GENOTYPE SPECIFIC PRIMERS

Abstract

Eight genotypes of hepatitis B virus are recognized which show deference in geographical distribution. Differences in genotypes affect the severity, complication, course and treatment of disease. This study was established in Sulaimani city, Kurdistan region, Iraq to detect HBV genotypes by rapid and specific method using PCR, which based on type specific primers. A total of 19 suspected hepatitis B patients including 14 males (73.68%) and 5 females (26.32%) were examined by PCR assay with universal outer primer used for detection of all HBV genotypes. The positive samples then examined by PCR assay using specific primers for each genotype. The result showed that 15 cases were negative and 4 cases were positives for HBV. The 4 positive HBV samples were subjected to genotyping. 4 genotypes (A, B, C, D) out of 6 genotypes, which can be determined by this method, were identified. Unique results were detected. Firstly, all of the samples showed mix infection, in which 1 case was mix genotype B+C+D and 3 cases were mix genotypes of A+B+C+ D. Secondly, sequencing of D genotype showed 120 nucleotide deletion mutations which encode overlapping gene of polymerase and pre-S protein. These results were not or rarely reported