Carr J K, Laukkanen T, Salminen M O, Albert J, Alaeus A, Kim B, Sanders-Buell E, Birx D L, McCutchan F E
Henry M. Jackson Foundation, Rockville, MD, USA.
AIDS. 1999 Oct 1;13(14):1819-26. doi: 10.1097/00002030-199910010-00003.
To improve our understanding of the genetic complexity of HIV-1 subtype A by increasing the number of subtype A isolates that have been sequenced in their entirety.
Nine HIV-1-seropositive patients from Africa living in Sweden contributed peripheral blood mononuclear cells (PBMC) for this study. Sequencing of the C2-V3 region of env had shown them to be subtype A. DNA from virus cultures was used for the amplification of virtually full-length proviral sequences, and the resulting fragment was sequenced.
Six of the nine viral isolates were subtype A throughout the genome, or non-recombinant, and all of these were from east Africa. One virus from the Ivory Coast had the AG(IbNG) genetic form, a recombinant form common in west Africa. Two of the isolates were novel recombinants: one was an A/C recombinant and the other was A/D. Analysis of gag reveals three subclusters within the A subtype: one containing the AG(IbNG) subtype viruses, one containing the AE(CM240) viruses and one containing the non-recombinant A viruses. These genetic clusters have different geographical distributions in Africa.
The prevailing view of HIV-1 subtype A forming a uniform band across the center of sub-Saharan Africa needs revision. In all probability, the most common subtype in west Africa and west central Africa is the AG recombinant, AG(IbNG), whereas in east central Africa it is the non-recombinant subtype A.
通过增加已完成全基因组测序的HIV-1 A亚型分离株数量，加深我们对HIV-1 A亚型基因复杂性的理解。
九名居住在瑞典的非洲HIV-1血清阳性患者为本研究提供了外周血单核细胞（PBMC）。env基因C2-V3区域的测序显示他们为A亚型。病毒培养物中的DNA用于扩增几乎全长的前病毒序列，并对所得片段进行测序。
九个病毒分离株中有六个在整个基因组中为A亚型，即非重组型，且所有这些均来自东非。来自象牙海岸的一种病毒具有AG（IbNG）基因形式，这是一种在西非常见的重组形式。其中两个分离株是新型重组体：一个是A/C重组体，另一个是A/D重组体。对gag基因的分析揭示了A亚型内的三个亚群：一个包含AG（IbNG）亚型病毒，一个包含AE（CM240）病毒，一个包含非重组A病毒。这些基因簇在非洲具有不同的地理分布。
关于HIV-1 A亚型在撒哈拉以南非洲中部形成一条统一带型的普遍观点需要修正。很可能，西非和中西部非洲最常见的亚型是AG重组体AG（IbNG），而在东中部非洲则是非重组A亚型。
