Genotyping of hepatitis B virus - Genotypes a to G by multiplex polymerase chain reaction

Objectives: Eight genotypes (A-H) of hepatitis B virus (HBV) are known with variations in nucleotide sequences greater than 8%. Several recent publications found that the clinical course and outcome of antiviral therapy depended on the genotype of the infecting HBV strain. Large epidemiological studies will require the availability of a system which is rapid, reliable and can be performed on a large number of samples. Methods: To establish a simple and accurate genotyping method, the study collected 369 HBV complete genomic sequences from the GenBank database. Type-specific primers were also designed that separated HBV genotypes A to G by multiplex polymerase chain reaction. Results: By comparison with the traditional restriction fragment length polymorphism method, over 93% of 441 samples were accurately genotyped by current assay, with a higher detection rate and sensitivity to detect mixed HBV infections. Conclusions: This methodology can be applied only to areas prevalent with HBV genotypes A to G. However, it provides an efficient alternative for clinical diagnosis and large-scale studies.