Cong M, Fried M W, Lambert S, Lopareva E N, Zhan M, Pujol F H, Thyagarajan S P, Byun K S, Fields H A, Khudyakov Y E
Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Atlanta, Georgia, 30333, USA.
Virology. 1999 Mar 15;255(2):250-9. doi: 10.1006/viro.1998.9592.
Two sets of primers derived from the 5'-terminal region and the NS5 region of the hepatitis G virus (HGV) genome were used to amplify PCR fragments from serum specimens obtained from different parts of the world. All PCR fragments from the 5'-terminal region (5'-PCR, n = 56) and from the NS5 region (NS5-PCR, n = 85) were sequenced and compared to corresponding published HGV sequences. The range of nucleotide sequence similarity varied from 74 and 78% to 100% for 5'-PCR and NS5-PCR fragments, respectively. Additionally, five overlapping PCR fragments comprising an approximately 2.0-kb structural region of the HGV genome were sequenced from each of five sera obtained from three United States residents. These sequences were compared to 20 published sequences comprising the same region of the HGV genome. Nucleotide and deduced amino acid sequences obtained from different individuals were homologous from 82.9 to 93. 6% and from 90.4 to 99.0%, respectively. Sequences obtained from follow-up specimens were almost identical. Comparative analysis of deduced amino acid sequences of the HGV structural proteins and hepatitis C virus (HCV) structural proteins combined with an analysis of predicted secondary structures and hydrophobic profiles allowed prediction of processing sites within the HGV structural proteins. A phylogenetic sequence analysis performed on the 2.0-kb structural region supports the existence of three previously identified HGV genetic groups. However, phylogenetic analysis performed on only small DNA fragments yielded inconsistent genetic grouping and failed to confirm the existence of genetic groups. Thus, in contrast to HCV where almost any region can be used for genotyping, only large or carefully selected genome fragments can be used to identify consistent HGV genetic groups.
从庚型肝炎病毒（HGV）基因组的5'末端区域和NS5区域衍生出两组引物，用于扩增来自世界各地血清标本的PCR片段。对所有来自5'末端区域的PCR片段（5'-PCR，n = 56）和来自NS5区域的PCR片段（NS5-PCR，n = 85）进行测序，并与已发表的相应HGV序列进行比较。5'-PCR和NS5-PCR片段的核苷酸序列相似性范围分别为74%至78%和78%至100%。此外，从三名美国居民的五份血清中分别对包含HGV基因组约2.0 kb结构区域的五个重叠PCR片段进行了测序。将这些序列与包含HGV基因组相同区域的20个已发表序列进行比较。不同个体获得的核苷酸和推导氨基酸序列的同源性分别为82.9%至93.6%和90.4%至99.0%。随访标本获得的序列几乎相同。对HGV结构蛋白和丙型肝炎病毒（HCV）结构蛋白的推导氨基酸序列进行比较分析，并结合对预测二级结构和疏水图谱的分析，从而预测HGV结构蛋白内的加工位点。对2.0 kb结构区域进行的系统发育序列分析支持先前确定的三个HGV遗传组的存在。然而，仅对小DNA片段进行的系统发育分析产生了不一致的遗传分组，未能证实遗传组的存在。因此，与HCV几乎任何区域都可用于基因分型不同，只有大的或精心选择的基因组片段才能用于识别一致的HGV遗传组。
