Population-specific patterns of heritability and integration in the human dentition

对于古人类学家和考古学家来说，牙齿是一种非凡的资源。它们在化石和考古记录中保存完好，包含了大量关于饮食、环境、生长和发育以及种群或物种之间的亲缘关系的信息。然而，影响牙齿形态多样性的潜在生物学过程尚未完全确定。该项目使用来自不同生物区域样本的牙科铸型样本和家谱，以更好地了解影响个体牙齿、个体牙列内牙齿和人类群体中形状特征表达的因素。这个项目的发现将促进人们对牙齿形成是如何由基因、发育和童年环境塑造的了解。研究人员将创建一个高分辨率3D牙齿扫描和匿名家谱的档案，这些档案将在网上托管，并免费提供给全球学者网络。该档案不仅将加强生物学家和人类学家的研究和教育基础设施，而且还将加强在应用领域进行初步研究的临床牙医、正畸医生和法医牙科医生的研究和教育基础设施。此外，这项工作还支持亚利桑那州立大学的本科生和研究生培训，亚利桑那州立大学是一个多元化和包容性的环境，西班牙裔和美洲原住民学生的比例很高。这项研究使用了对哺乳动物牙冠特征的牙冠、牙尖和皱纹的测量和观察。尽管许多学者在不同的领域使用它们，但我们仍然不完全了解牙齿形成过程是如何受到基因控制的，以及牙列中不同的牙齿是如何在包括遗传和非遗传因素的发育过程中整合的。在这个项目中，将从代表不同现代人群体的五个样本中的大约3000个个体中每个人收集150-250个观察数据。定量遗传分析将被用来估计基因和环境在决定牙齿大小和形状(遗传力)变异方面的相对贡献。尺寸和形状变量之间的遗传相关性(多效性)的估计将定义生物体如何在同一发育计划下的不同时间(子宫内和儿童早期)形成类似的组织(牙齿)，并利用重叠的遗传因素进行输入。这些估计值将在五个种群中进行比较，以评估是否存在普遍的人类模式，如果不明显，则确定哪些因素可以解释种群之间的差异。研究结果将深入了解研究人员如何将牙齿数据用作基因替代测量，重点是考古或法医背景下的牙齿使用。这一奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Teeth are an extraordinary resource for paleoanthropologists and archaeologists. They preserve well in the fossil and archaeological records, and contain a great deal of information about diet, environment, growth and development, and relatedness among populations or species. However, the underlying biological processes influencing diversity in tooth form have yet to be fully established. This project uses dental cast samples and family genealogies from diverse bioregional samples to better understand the factors that influence the expression of shape characteristics on an individual tooth, among teeth within an individual's dentition, and among human populations. The findings from this project will advance knowledge about how tooth formation is shaped by genes, development, and childhood environment. The investigators will create an archive of high resolution 3D tooth scans and anonymized genealogies that will be hosted online and made freely available to a global network of scholars. This archive will enhance the research and educational infrastructure for not only biologists and anthropologists, but also clinical dentists, orthodontists, and forensic odontologists who conduct primary research in applied fields. Additionally, the work supports undergraduate and graduate student training at Arizona State University, a diverse and inclusive environment with a high representation of Hispanic and Native American students.This research uses measurements and observations on the crests, cusps, and furrows that characterize mammalian tooth crowns. Despite their use by numerous scholars across diverse fields, we still do not fully understand how the process of tooth formation is genetically controlled and how different teeth within the dentition are integrated with respect to developmental processes that include both genetic and non-genetic factors. In this project, 150-250 observations will be collected from each of approximately 3,000 individuals from five samples representing distinct modern human populations. Quantitative genetic analyses will be used to estimate the relative contribution of genes and environment in determining variation in tooth size and shape (heritability). Estimates of genetic correlation (pleiotropy) among dimensions and shape variables will define how an organism forms similar tissues (teeth) at different times (in-utero versus early childhood) under the same developmental program and with input from overlapping genetic factors. These estimates will be compared across the five populations to assess whether a general human pattern is evident, and if not, to determine what factors explain disparities between populations. Results will yield insights into how researchers can use dental data as a genetic proxy measure, with an emphasis on the use of teeth from archaeological or forensic contexts.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.