Van Dooren S, Gotuzzo E, Salemi M, Watts D, Audenaert E, Duwe S, Ellerbrok H, Grassmann R, Hagelberg E, Desmyter J, Vandamme A M
Rega Institute for Medical Research, KU Leuven, Belgium.
J Gen Virol. 1998 Nov;79 ( Pt 11):2695-708. doi: 10.1099/0022-1317-79-11-2695.
To investigate the origin and dissemination of human T-cell lymphotropic virus type I in Latin America, we performed phylogenetic analysis on the LTR and env sequences of 13 HTLV-I isolates from Peruvians of four different ethnic groups: blacks and some mulattos of African origin; Quechuas of Inca origin; Nikkei of Japanese descendance; and Mestizos, a mixed population of white and Indian origin. All Peruvian samples could be situated within the cosmopolitan subtype HTLV-Ia, yet one sample showed an indeterminate Western blot pattern, lacking reactivity towards the HTLV-I type specific MTA1 peptide. Within the LTR, we could confirm the previously reported subdivision into four subgroups--one big transcontinental clade A, a Japanese clade B, a West African/Caribbean clade C and a North African clade D--and we identified a new separate subgroup E of black Peruvian strains. The clustering of the Peruvian samples seemed to depend on the ethnic origin of the host. The largest heterogeneity was observed in the black Peruvian samples. The mitochondrial DNA type of one of these black Peruvian strains of subgroup E was identical to that of West African source populations of the slave trade. Both findings support the idea of multiple post-Columbian introductions of African HTLV-Ia strains into the black Latin American population. Additionally, a tight cluster of Nikkei and Japanese samples implied a separate and rather recent transmission of a Japanese lineage of HTLV-I into Peru. A well-supported cluster of Latin American strains (including Peruvian Quechuas and Colombian Amerindians) could be situated within the transcontinental group. Molecular clock analysis of the Latin American and Japanese clade resulted in an equal evolutionary rate for those strains. Along with the anthropologically documented peopling of the Americas, the analysis was more in favour of a recent (400 to 100 years ago) introduction of HTLV-Ia into the American continent rather than a Palaeolithic introduction.
为了研究I型人类嗜T细胞病毒在拉丁美洲的起源和传播，我们对来自四个不同种族秘鲁人的13株HTLV-I分离株的长末端重复序列（LTR）和包膜基因（env）序列进行了系统发育分析，这四个种族分别是：非洲裔黑人及部分混血儿；印加起源的克丘亚人；日本后裔的日裔秘鲁人；以及白人-印第安人混血的梅斯蒂索人。所有秘鲁样本都属于世界流行的HTLV-Ia亚型，但有一个样本的蛋白质印迹法结果不确定，对HTLV-I型特异性MTA1肽缺乏反应性。在LTR区域，我们证实了之前报道的分为四个亚组的分类——一个大的跨大陆进化枝A、一个日本进化枝B、一个西非/加勒比进化枝C和一个北非进化枝D——并且我们鉴定出了一个新的、单独的秘鲁黑人毒株亚组E。秘鲁样本的聚类似乎取决于宿主的种族起源。在秘鲁黑人样本中观察到最大的异质性。亚组E的这些秘鲁黑人毒株之一的线粒体DNA类型与奴隶贸易中的西非来源人群相同。这两个发现都支持了后哥伦布时代非洲HTLV-Ia毒株多次传入拉丁美洲黑人人群的观点。此外，日裔秘鲁人和日本样本的紧密聚类意味着HTLV-I的日本谱系有一次单独且相当近期的传入秘鲁的传播。一个得到充分支持的拉丁美洲毒株聚类（包括秘鲁克丘亚人和哥伦比亚美洲印第安人）可以位于跨大陆组内。对拉丁美洲和日本进化枝的分子钟分析得出这些毒株的进化速率相同。结合人类学记录的美洲人口迁移情况，该分析更支持HTLV-Ia在近期（400至100年前）传入美洲大陆，而非旧石器时代传入。
