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

作为生物物种，人类通过自然选择继续从基因上适应各种环境。然而，文化和生活方式的变化比生物变化发生得快得多，在某些情况下，导致我们的生物和现代生活之间的不匹配。这个博士论文项目调查了两个群体(觅食者和农牧民)过去食物资源的差异如何导致新陈代谢中不同的基因适应，以及这些适应可能如何与现代幸福和慢性疾病相关。这位研究人员假设，当一个人过渡到现代饮食和生活方式时，过去对驯化食物的基因适应可能会导致较少的慢性健康问题。这项研究将有助于我们理解饮食在人类进化和适应中的作用，以及它对当代人群幸福感的影响。来自美洲印第安人的遗传、流行病学和文化数据将与参与者和利益攸关方以及科学界共享，这些数据对于了解基因组变异在混血人群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，并为研究生和本科生水平的学生培训做出贡献。基于人类生物学、营养和分子人类学以及进化医学的文献，这项拟议的研究旨在(1)评估参与营养代谢的基因组区域是否通过在两个生存策略(狩猎-采集和农牧)历史不同的美洲印第安人群体中的选择而成为不同的靶标，以及(2)评估这些特征是否具有生存专一性，以及是否与几种慢性病风险生物标记物的流行相对应。问题是，相对较新的饮食变化是否对人类人口产生了进化影响，以及这些变化与营养过渡后人口慢性病的增加在多大程度上有关。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从事狩猎采集活动，另一个长期在沙漠环境中从事农牧业。研究设计将包括人种学实地工作，包括口述历史访谈、饮食和体力活动调查、血液和人体测量慢性病风险生物标记物的测量，以及全基因组扫描以供选择。

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.