We have cloned the HBV genome subtype adr through its HindⅢ site into plasmid pBR.322. Twelve recombinant plasmids each with an insert of the HBV genome were obtained. The restriction map of one of the recombinants, plasmid pADR-H1, was analyzed. The location of the sites for BamHⅠ, BglⅠ, BglⅡ, SstⅡ, XbaⅠ and XhoⅠ in pADR-HⅠ were found to be the same as that in pADR-1, but the HindⅢ site of pADR-H1 is distinctly different from that of pADR-1. The BamHⅠ-HindⅢ fragment is 316 bp long in the gcnome of pADR-1. However, it is only 82 bp in pADR-Hl. No deletion of sequence between BamHⅠ and HindⅢ sites has been found in the HBV genome of pADR-H1, The sequencing data around the HindⅢ site of pADR-H1 in both pADR-H1 and pADR-1 show that there is a stretch of AAGTTT in pADR-1 compared to an AAGCTT in pADR-H1. In addition, other differences were found. There are three sites for AvaⅠ, four for HincⅡ, one for HpaⅠ and none for SphⅠ in the genome of pADR-H1 compared to four sites for AvaⅠ, three f We have cloned the HBV genome subtype adr through its Hind III site into plasmid pBR.322. The restriction map of one of the recombinants, plasmid pADR-H1, was analyzed. The location of the sites for BamHI, BglI, BglII, SstII, XbaI and XhoI in pADR-Hl were found to be the same as that in pADR-1 but the HindIII site of pADR-Hl was distinctly different from that of pADR-I However, it is only 82 bp in pADR-H1. No deletion of sequence between BamHI and HindIII sites has been found in the HBV genome of pADR-H1 , The sequencing data around the Hind III site of pADR-H1 in both pADR-H1 and pADR-1 show that there is a stretch of AAGTTT in pADR-1 compared to an AAGCTT in pADR-H1. In addition, other differences were found. There are three sites for Ava I, four for Hinc II, one for Hpa I and none for Sph I in the genome of pADR-H in compa red to four sites for AvaⅠ, three f