Genetic analysis of HIV/SIV and HTLV/STLV in Africa -Elucidation of Their Origins and Evolution

这两个灵长类逆转录病毒组，HIV/SIV和HTLV/STLV，现在已知彼此在基因上有亲缘关系，并构成一个巨大的病毒超家族。关于这两组病毒的遗传分析和传播方式的积累知识表明，这两组病毒似乎都是通过人畜共患病传播的。为了阐明这两个病毒组的起源和进化，我们对艾滋病患者、健康人和中部非洲(喀麦隆、刚果共和国和刚果民主共和国)的少数民族俾格米人进行了血清调查和系统发育分析。俾格米人的血清回收率出人意料地低，根据分离的病毒的基因数据，如果有的话，病毒被认为是从邻近的班图居民传播的。对艾滋病患者HIV-1的详细基因分析表明，病毒基因组不仅高度多样化，而且经常嵌合，这意味着基因组大多是重组形式。通过对不同种类猴的调查，我们首次从刚果民主共和国捕获的黑尾猴中分离到一株新的SIV。这种病毒(SIVblm)的系统发育位置非常独特，有趣的是，它的Poll基因组区域(RNAseH)的一部分在遗传上与最古老的HIV 1毒株之一蚂蚁毒株的遗传非常接近，这表明目前的HIV 1基因组可能是镶嵌的，其起源部分来自这个猴子物种。

The two primate retrovirus groups, HIV/SIV and HTLV/STLV, are now known to be genetically related each other and constitute a huge viral superfamily. Accumulated knowledges on the genetical analyses and the way of transmission of these two viral groups indicated that both groups appear to have been transmitting zoonotically. To elucidate the origins and evolution of these two virus groups, we conducted serosurveys and phylogenetic analyses of these viruses among AIDS patients, healthy persons, and Pygmy people, an ethnic minority in Central Africa (Cameroon, Republic of Congo, and Democratic Republic of Congo).Seroprevalece of Pygmies was unexpectedly low, and the viruses, if any, were considered to have been transmitted from neighboring Bantu residents judged from genetic data of the isolated ones. Detailed genetic analyses of HIV-1 from AIDS patients have revealed that the viral genomes are not only highly diversified but also frequently mosaic, which means that the genomes are mostly recombinant forms. From the survey among various monkey species, we firstly isolated a new SIV from black mangabeys captured in Democratic Republic of Congo. The phylogenetic position of this virus (SIVblm) is very unique, and interestingly a part of its pol genomic region (RnaseH) is genetically very close to that of the Ant strain, one of the oldest HIV 1 strain, suggesting that the genome of present HIV 1 might be mosaic and its origin is partly from this monkey species.