Background: There are eight genotypes (A-H) and numerous subgenotypes of hepatitis B virus (HBV). The genotype has been shown to affect the course of HBV infection.
Objectives: To develop an efficient genotyping and subgenotyping method for large-scale epidemiological surveys of HBV infection in countries with high prevalence of HBV B and C such as China.
Study design: We designed genotype and subgenotype-specific primer pairs, and adjusted PCR conditions for a multiplex-PCR using common Taq polymerase to identify HBV genotypes A-F in one reaction and for the main subgenotypes B1/B2 and C1/C2 in another reaction.
Results: We have developed a multiplex-PCR system, which specifically amplifies DNA of HBV genotypes and the corresponding main subgenotypes B and C from the sera of HBV patients. Our patients were infected with HBV of subgenotypes B2 (n=18), C1 (n=2) and C2 (n=48). Eleven patients were doubly infected and three showed a triple infection with HBV A, B and C.
Conclusions: The low-cost multiplex-PCR for identification of HBV genotypes A-F and main subgenotypes of HBV B and C, is rapid, reliable and sufficient for large-scale epidemiological surveys and clinical studies.