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从我国河南、内蒙、北京等地的ＨＤＶ健康携带者、慢性丁肝病人与重症肝炎病人中，筛选获得４份ＨＤＶ—ＲＮＡ阳性血清。经逆转录—聚合酶链反应（ＲＴ—ＰＣＲ）交叉扩增获得ＨＤＶ—ｃＤＮＡ片段（６５１—１６６０ｎｔ，按Ｍａｋｉｎｏｅｔａｌ定位），并克隆到ＰＧＥＭ—３ｚｆ（－）或ＰＧＥＭ－Ｔ载体上。经序列分析研究其基因结构特点，结果表明，同属基因Ⅰ型的４株中国丁型肝炎病毒，在基因序列上具有相似的保守区域，但与同亚型ＨＤＶ健康携带者相比，重症肝炎病人与慢性丁肝病人来源的ＨＤＶ毒株，在多个位点上发生了核苷酸的改变，由此推导的抗原编码区相应的氨基酸发生了替换。这些核苷酸与氨基酸的改变位点散在，但多集中于抗原编码区的羧基端。如慢性丁肝发生的６个氨基酸改变中，５个位于１６６—１８８位；重症肝炎发生的１２个氨基酸改变中，８个位于１７０—２１４位。有趣的是，在１７５位上发生了由脯氨酸向丝氨酸的共同替换。提示ＨＤＶ的感染致病可能与ＨＤＶ的基因结构相关。
Four HDV-RNA positive sera were screened from HDV healthy carriers, chronic hepatitis D patients and severe hepatitis patients in Henan, Inner Mongolia and Beijing. The HDV-cDNA fragment (651-1660 nt, mapped by Makino et al) was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into PGEM-3zf (-) or PGEM-T vector. The results of sequence analysis showed that four Chinese hepatitis D viruses with the same genotype Ⅰ had similar conserved regions in gene sequence, but compared with healthy carriers of subtype HDV, severe hepatitis patients In contrast to HDV strains from chronic hepatitis C patients, nucleotide changes occur at multiple sites, and the corresponding amino acids in the deduced antigen coding region are replaced. These nucleotide and amino acid sites are interspersed with alterations, but most are concentrated at the carboxy terminus of the antigen coding region. Among the six amino acid changes that occur in chronic hepatitis B, five are located between 166 and 188; among the 12 amino acid changes that occur in severe hepatitis, eight are located between 170 and 214. Interestingly, a common substitution of proline to serine occurred at position 175. Tip HDV infection pathogenesis may be related to the genetic structure of HDV.