Population Structure of Schistosomes and Host Snails

血吸虫和寄主钉螺的种群结构

• 批准号: 6683092
• 负责人: DENNIS J. MINCHELLA
• 金额: $ 30.4万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-02-01 至 2004-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6683092
• 关键词: Gastropoda; Schistosoma; animal genetic material tag; biochemical evolution; field study; gene expression; gene frequency; genetic markers; genetic polymorphism; genotype; host organism interaction; laboratory mouse; mathematical model; phenotype; polymerase chain reaction; population genetics; virulence

DESCRIPTION (provided by the applicant): Interactions between schistosomes and their snail hosts play an important role in the evolutionary development of the host and parasite genetic systems. Gene flow, genetic drift and selection all potentially act on host-parasite interactions, driving co-evolutionary trajectories and dictating disease dynamics. Assessing the degree and structure of genetic heterogeneity of both participants in a host-parasite interaction is an essential first step in gaining predictive power over epidemiology. The recent characterization of microsatellite markers for Schistosoma mansoni and Biomphalaria glabrata provides an opportunity to study population structure of both host and parasite on a local spatial scale, using markers that exhibit allelism. Specific aims include: 1) Determine the relative nature of population subdivision for schistosomes and their snail host populations based on allelic data from microsatellites, and assess how that genetic variation changes on both a spatial and temporal scale; and 2) Correlate microsatellite allelic heterogeneity with biomarkers for schistosome virulence and snail resistance to assess the relationship between genetic variation and phenotypic characters of epidemiological importance. Knowledge of the distribution of host and parasite genetic diversity within and among individual hosts, and within and among populations, will allow us to estimate parasite gene flow, assess the importance of multiple genotypes on parasite virulence, and begin to understand the interplay of micro-evolutionary forces that drive disease dynamics. Results will yield evolutionary insights into the epidemiological process, help identify genetic consequences of control strategies, and complement concurrent immuno-epidemiology studies of humans in endemic Brazilian communities.

描述(由申请人提供)：血吸虫与其蜗牛宿主之间的相互作用在宿主和寄生虫遗传系统的进化发展中发挥着重要作用。基因流、遗传漂移和选择都可能作用于宿主和寄生虫的相互作用，推动共同进化轨迹并决定疾病动态。评估宿主-寄生虫相互作用中两个参与者的遗传异质性的程度和结构是获得对流行病学的预测能力的关键的第一步。最近对曼氏血吸虫和光滑生物微卫星标记的表征为利用显示等位基因的标记在局部空间尺度上研究宿主和寄生虫的种群结构提供了机会。具体目标包括：1)根据来自微卫星的等位基因数据，确定血吸虫及其钉螺宿主种群划分的相对性质，并评估这种遗传变异在空间和时间尺度上的变化；以及2)将微卫星等位基因异质性与血吸虫毒力和钉螺抗性的生物标志物相关联，以评估遗传变异与具有流行病学意义的表型特征之间的关系。了解宿主和寄生虫遗传多样性在单个宿主内和宿主之间的分布，以及在种群内和种群之间的分布，将使我们能够估计寄生虫的基因流，评估多种基因类型对寄生虫毒力的重要性，并开始了解驱动疾病动态的微观进化力量的相互作用。结果将产生对流行病学过程的进化洞察，帮助确定控制策略的遗传后果，并补充对巴西流行社区人类的同时免疫流行病学研究。