Doctoral Dissertation Research: The effects of past dietary adaptations on modern populations

作为一个生物物种，人类通过自然选择继续在基因上适应各种环境。然而，文化和生活方式的变化发生得比这些生物变化快得多，在某些情况下导致我们的生物学和现代生活之间的不匹配。这个博士论文项目研究了两个种群（觅食者与农牧者）过去食物资源的差异如何导致代谢中不同的遗传适应，以及这些适应如何与现代健康和慢性疾病有关。研究人员假设，当人口过渡到现代饮食和生活方式时，过去对驯化食品的遗传适应可能会导致更少的慢性健康问题。 这项研究将有助于我们了解饮食在人类进化和适应中的作用，以及它对当代人群福祉的影响。将与与会者和利益攸关方以及科学界分享美洲印第安人的遗传、流行病学和文化数据，这些数据对于了解基因变异在混合人口现代福祉中的作用至关重要。这项调查将包括来自代表性不足的群体的个人作为研究参与者和研究人员，建立和加强国际研究合作，并有助于在研究生和本科生水平的学生培训。以人类生物学、营养和分子人类学以及进化医学的文献为基础，该研究计划的目的是：（1）在两个营养转型后的美洲印第安人群体中，评估参与营养代谢的基因组区域是否被选择作为不同的目标，这两个群体具有不同的生存策略历史（2）评估这些特征是否具有生存特异性，是否与几种慢性病风险生物标志物的流行程度相对应。问题是，相对较新的饮食变化是否对人类种群产生了进化后果，以及这些变化在多大程度上与营养转型后人群慢性病的增加有关。这项研究将包括两个美洲印第安人群体：一个直到最近还在温带森林中从事狩猎采集，另一个长期在沙漠环境中从事农牧活动。研究设计将包括民族志实地考察，包括口述历史访谈，饮食和身体活动调查，血液和人体测量慢性疾病风险生物标志物的测量，以及全基因组扫描选择。

As a biological species, humans continue to adapt genetically to various environments through natural selection. However, cultural and lifestyle changes occur much more rapidly than those biological changes, leading in some cases to a mismatch between our biology and our modern life. This doctoral dissertation project investigates how past differences in the food resources of two populations (foragers vs. agropastoralists) may have led to different genetic adaptations in metabolism, and how those adaptations may relate to modern-day well-being and chronic conditions. The investigator hypothesizes that past genetic adaptations to domesticated foodstuffs could result in fewer chronic health problems when a population transitions to a modern diet and lifestyle. The study will contribute to our understanding of the role of diet in human evolution and adaptation, and its effects on well-being in contemporary populations. Genetic, epidemiological and cultural data from Amerindian individuals, which are crucial for understanding the role of genomic variants in modern well-being among admixed populations, will be shared with participants and stakeholders as well as the scientific community. This investigation will include individuals from underrepresented groups as both research participants and researchers, build and strengthen international research collaborations, and contribute to student training at the graduate and undergraduate levels. Grounded in the literature of human biology, nutritional and molecular anthropology, and evolutionary medicine, the proposed research aims to (1) evaluate whether genomic regions involved in nutrient metabolism have been differentially targeted by selection in two post-nutrition transition Amerindian populations with contrasting histories of subsistence strategies (hunting-gathering vs. agropastoralism) and (2) evaluate whether these signatures are subsistence-specific and correspond to the prevalence of several chronic condition risk biomarkers. The question arises as to whether relatively recent dietary shifts have had evolutionary consequences for human populations, and to what extent these are related to the rise in chronic conditions in post-nutrition transition populations. This study will include two Amerindian populations: one that until recently engaged in hunting-gathering in the temperate forest, and the other that has been long engaged in agropastoralism in a desert environment. The research design will comprise ethnographic fieldwork including oral history interviews, dietary and physical activity surveys, measurements of blood and anthropometric chronic condition risk biomarkers, and genome-wide scans for selection.