Multilocus sequence typing reveals three genetic subpopulations of Cryptococcus neoformans var. grubii (Serotype A), including a unique population in Botswana
Multilocus sequence typing reveals three genetic subpopulations of Cryptococcus neoformans var. grubii (Serotype A), including a unique population in Botswana
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DOI：
10.1534/genetics.105.046672
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发表时间：
2006-04-01
期刊：
影响因子：
3.3
通讯作者：
Mitchell, TG
中科院分区：
文献类型：
--
作者：
Litvintseva, AP;Thakur, R;Mitchell, TG
我们应用多位点序列分型（MLST）来研究新型隐球菌的种群结构和繁殖方式。 grubii（血清型 A）。该MLST系统利用分散在9个不同染色体上的12个不连锁的多态性位点，并且可以明确地鉴定密切相关的A血清型菌株。我们将MLST分析与检测扩增片段长度多态性(AFLP)的传统基因分型方法进行比较，MLST和AFLP结果之间存在极好的相关性。然而，MLST 区分了更多的菌株。我们使用这两种方法分析了全球 A 血清型分离株，结果鉴定出至少三个遗传上不同的亚群，指定为 VNI、VNII 和 VNB 组。 VNI 和 VNII 群分布广泛，以 MAT α 交配型分离株为主，且以克隆为主。相反，VNB 群的分离株是博茨瓦纳特有的，包括相当大比例的具有 MAT α 交配类型的可育菌株，并且表现出令人信服的重组证据。我们对来自世界不同地区的超过 1000 株 A 血清型菌株进行了 AFLP 基因分型，其中包括来自几个非洲国家的分离株，迄今为止，仅在博茨瓦纳发现了 VNB 组的单倍体 A 血清型分离株。
We applied multilocus sequence typing (MLST) to investigate the population Structure and mode of reproduction of Cryptococcus neoformans var. grubii (serotype A). This MLST system utilizes 12 unlinked polymorphic loci, which are dispersed on nine different chromosomes, and allows the unambiguous identification of closely related strains of serotype A. We compared MLST analyses with the conventional genotyping method of detecting amplified fragment length polymorphisms (AFLPs), and there was excellent correlation between the MLST and AFLP results. However, MLST differentiated a larger number of strains. We analyzed a global collection of isolates of serotype A using both methods, and the results identified at least three genetically distinct subpopulations, designated groups VNI, VNII, and VNB. Groups VNI and VNII are widespread, dominated by isolates with the MAT alpha mating type, and predominantly clonal. Conversely, isolates of group VNB are unique to Botswana, include a significant proportion of fertile strains with the MAT alpha mating type, and manifest compelling evidence of recombination. We have AFLP genotyped > 1000 strains of serotype A from different parts of the world, including isolates from several African countries, and, to date, haploid serotype A isolates of group VNB have been found only in Botswana.