Mixed peoples, mixed microbes: Human and Helicobacter pylori coevolution in the European-African population of Cape Verde

混合民族，混合微生物：佛得角欧洲-非洲人群中的人类和幽门螺杆菌共同进化

• 批准号: 1791033
• 金额: --
• 依托单位: University of Leicester
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-1791033
• 关键词: Mixed; peoples; mixed; microbes; Human

Helicobacter pylori (HP) infection is one of the most common bacterial infections in the world, and is known to have been co-evolving with humans since their origins in Africa ~100,000 years ago. Due to this, bacteria from around the world are genetically stratified as their hosts are. HP has a dynamic genome exhibiting intra-host genomic variation as it evolves in response to the selective pressures of the host, which can inclusively lead to the expression of specific types and combinations of virulence factors and ultimately disease. Several studies on within-host evolution showed the pivotal role of recombination in genomic diversification of HP, especially in the presence of infection with multiple strains. These studies have also shown that recombination rates are different among stains. Although these studies have only started to disclose general patterns of microevolution of HP. The aim of this project is to investigate the patterns of HP microevolution in a cohort from Cape Verde, a population that derives mixed ancestry from Europe and West Africa. Due to the random recombination that occurs over the generations since the first admixture event, present day admixed genomes (both host and HP genomes) in Cape Verde consist of mosaics of segments with European and African ancestry that are relatively easily to trace computationally. We can explore this property to characterize the history of recombination of HP and its role in the generation of diversification in HP. The specific aim is to characterize the genomic variation of up to 5 bacterial isolates from each of 80-100 infected Cape Verdeans and to use this data to infer the haplotypic structure of the isolates in terms of the number of blocks of African and European ancestry (so called inference of local ancestry), and to evaluate the role of admixture and recombination in generating bacterial diversity within and among individuals in the general population of Cape Verde.

幽门螺杆菌（HP）感染是世界上最常见的细菌感染之一，并且已知自10万年前起源于非洲以来一直与人类共同进化。因此，来自世界各地的细菌在遗传上与它们的宿主一样分层。HP具有动态基因组，其在响应于宿主的选择压力而进化时表现出宿主内基因组变异，这可包括性地导致特定类型和毒力因子组合的表达并最终导致疾病。宿主内进化的一些研究表明，重组在HP基因组多样化中起着关键作用，特别是在存在多株感染的情况下。这些研究还表明，菌株之间的重组率是不同的。尽管这些研究只是开始揭示HP微进化的一般模式。该项目的目的是调查来自佛得角的一个队列中HP微进化的模式，该人群来自欧洲和西非的混合祖先。由于自第一次混合事件以来发生的世代随机重组，佛得角现今的混合基因组（宿主和HP基因组）由具有欧洲和非洲血统的片段的镶嵌组成，这些片段相对容易通过计算追踪。我们可以探索这一特性，以描述惠普的重组历史及其在惠普多元化产生中的作用。具体目标是描述来自80 - 100名感染佛得角人的每一个的多达5个细菌分离物的基因组变异，并使用该数据来推断分离物在非洲和欧洲祖先的块数方面的单倍型结构（所谓的地方血统推断），并评估混合和重组在佛得角一般人群中产生细菌多样性的作用。