Pardi D, Hjelle B, Folks T M, Lal R B
Retrovirus Diseases Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA.
Virus Genes. 1995;10(1):27-35. doi: 10.1007/BF01724294.
The Amerindian human T-cell lymphotropic virus type II isolate HTLV-IIG12 has been demonstrated to be an HTLV-IIb with several unique features, including several restriction enzyme site changes, a distinctive pre-gag region, a stop codon within the pol gene, and an extended Tax protein. In this study, HTLV-II isolates from Amerindian and non-Indian populations were characterized by restriction enzyme site analysis to determine the prevalent HTLV-II subtype. In addition, DNA amplification by the polymerase chain reaction and Southern blot analyses were used to probe for the HTLV-IIG12 pre-gag region. Our results showed that of 13 Guaymi Indian isolates subtyped, all were HTLV-IIb, and that approximately one third of 17 isolates had the unique pre-gag region. While other HTLV-II-infected groups contained both HTLV-IIa and HTLV-IIb isolates, none of these isolates showed evidence of the distinctive HTLV-IIG12 pre-gag region. Lastly, DNA sequence analysis was used to determine the prevalence of the stop codon within the pol gene open reading frame. These analyses revealed that the occurrence of a stop codon within this sequence appeared to be characteristic of most HTLV-IIb subtypes. These results further our understanding of the genetic variations and evolution of the HTLV-II viruses within the endemically infected Amerindian populations, as well as U.S. intravenous drug users and other non-Indian populations.
美洲印第安人人类嗜T细胞病毒II型分离株HTLV - IIG12已被证明是一种具有若干独特特征的HTLV - IIb，这些特征包括多个限制酶切位点变化、一个独特的前gag区域、pol基因内的一个终止密码子以及一个延长的Tax蛋白。在本研究中，通过限制酶切位点分析对来自美洲印第安人和非印第安人群的HTLV - II分离株进行了特征鉴定，以确定流行的HTLV - II亚型。此外，利用聚合酶链反应进行DNA扩增和Southern印迹分析来探测HTLV - IIG12前gag区域。我们的结果显示，在13个已分型的瓜伊米印第安人分离株中，全部为HTLV - IIb，并且17个分离株中约有三分之一具有独特的前gag区域。虽然其他HTLV - II感染组同时包含HTLV - IIa和HTLV - IIb分离株，但这些分离株均未显示出独特的HTLV - IIG12前gag区域的证据。最后，利用DNA序列分析来确定pol基因开放阅读框内终止密码子的流行情况。这些分析表明，该序列内终止密码子的出现似乎是大多数HTLV - IIb亚型的特征。这些结果进一步加深了我们对地方性感染的美洲印第安人群体以及美国静脉吸毒者和其他非印第安人群体内HTLV - II病毒遗传变异和进化的理解。
