Genetic diversity of feline immunodeficiency virus: Dual infection, recombination, and distinct evolutionary rates among envelope sequence clades
Genetic diversity of feline immunodeficiency virus: Dual infection, recombination, and distinct evolutionary rates among envelope sequence clades
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DOI：
10.1128/jvi.71.6.4241-4253.1997
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发表时间：
1997-06-01
影响因子：
5.4
通讯作者：
Mullins, JI
中科院分区：
文献类型：
--
作者：
Bachmann, MH;MathiasonDubard, C;Mullins, JI
为了对猫免疫缺陷病毒（FIV）进行快速遗传分析，我们开发了一种异双工迁移性测定（HMA），该方法利用pcr扩增的FIV包膜基因片段，跨越包膜表面蛋白编码序列的第三和第四个可变区域。从来自澳大利亚、加拿大、德国、意大利、南非和美国的98只自然感染猫的血液标本中成功扩增出病毒序列。其中80个可明确归属于A或B包膜序列亚型。其中3例属于C亚型，1例被携带A和B env亚型的病毒双重感染，有几例被归类为任何已建立的亚型的异常值或可能的亚型间重组。一些地理聚类是明显的，在美国西部和东部地区分别发现A和B亚型的频率更高。在不止一个大陆上发现了A、B和C亚型，分析了两个以上样本的国家至少含有两种亚型。亚型最广泛的代表是在德国慕尼黑发现的，在那里发现了三种亚型和一种无法分类的乙型肝炎病毒。选择了13个样本，在用于HMA的env相同区域进行DNA序列测定。分析本研究和以往研究中所有可用的FIV env序列，发现存在由A/B、B/D和A/C亚型包膜基因序列产生的重组病毒。A亚型环境序列的多样性低于B亚型序列，尽管两组都有良好的支持簇。此外，导致两种亚型多样化的突变模式不同，与亚型B相比，亚型A病毒显示的同义位点突变数量只有一半，但显示出相似水平的非同义位点变化。这些结果与FIV-B是一个更古老的病毒群的假设是一致的，并且可能比FIV-A更适应宿主。
For the rapid genetic analysis of feline immunodeficiency virus (FIV), we developed a heteroduplex mobility assay (HMA) that utilizes a PCR-amplified fragment of the FIV envelope gene spanning the third and fourth variable regions of the envelope surface protein coding sequence. Viral sequences were successfully amplified from blood specimens from 98 naturally infected cats from Australia, Canada, Germany, Italy, South Africa, and the United States. Eighty were clearly assignable to the A or B envelope sequence subtypes. Three belonged to subtype C, one was dually infected with viruses harboring the A and B env subtypes, and several were categorized as outliers to any of the established subtypes or as probable intersubtype recombinants. Some geographic clustering,vas evident, with subtypes A and B found in greater frequency in the western and eastern regions of the United States, respectively. Subtypes A, B, and C were found on more than one continent, and countries with more than two samples analyzed contained at least two subtypes. The broadest representation of subtypes was found in Munich, Germany, where three subtypes and one virus that was not classifiable blv HMA were found. Thirteen samples were selected for DNA sequence determination over the same region of env used for HMA. Analysis of all available FIV env sequences from this and previous studies revealed the existence of recombinant viruses generated from subtype A/B, B/D, and A/C envelope gene sequences. Subtype A env sequences were less diverse than subtype B sequences, although both groups had well-supported clusters. Furthermore, the mutational pattern giving rise to diversification in the two subtypes differed, with the subtype A viruses showing half as many synonymous site mutations compared to subtype B yet showing similar levels of nonsynonymous site changes. These results are consistent with the hypothesis that FIV-B is an older virus group and is possibly more host adapted than FIV-A.