Abstract: Tvector clones of HBV surface antigen of adr subtype which contain preS2 region were constructed and nucleic acid sequence was analyzed.Sera from hepatitis B patients were digested by protease Kand HBVgenomes were extracted by phenol and chloroform.The target gene was am plified from HBVgenome and PCR products were collected by agrose gel electrophoresis. The am plified gene was digested with agrase and ligated with Tvector directly.The ligation products were transformed into E.coli DH10b and the target sequence was analyzed.The results showed that 3 positive PCR products were obtained from 10 HBVgenomes ,and the positive clones belonged to HBVadr subtype ,there was more than 99.6 % homology with the published clone adr-1 and these clones provided a perfect contribution to the expression of vaccine and HBVadr subtype specialty.

Key words: HBsAg, preS2 gene, adr subtype, PCR, T-vector