Doctoral Dissertation Research: Biological Distance and the African American Dentition

每当两个人类群体接触时，基因流动就会发生。因此，几乎所有的人类种群在基因上都是动态的，它们的组成随着时间的推移而变化。非洲裔美国人是另外两个可识别的生物群体（西非人和欧洲裔美国人）之间基因流动的结果。这个项目将利用牙齿特征来追踪这三个群体之间的遗传关系。牙齿形态的特征，如铲形门牙和卡拉贝利特征，对这一目的是有用的，因为它们具有高度的遗传性，在生活中不会重塑（尽管它们可能因磨损或病理而丢失），并且可以在过去和现在的人群中进行平等的比较。本研究结果将为生物文化背景下的人类微进化提供新的认识。通过分析来自每个生物群体的各种样本，将通过时间和空间观察遗传变化的模式。此外，通过将本研究的信息与其他非裔美国人混合分析的信息进行比较，将有可能扩展我们对美国人口历史的了解。最后，本研究的结果将包括三组中每组的牙齿特征频率表。非裔美国人和欧洲裔美国人目前还没有这方面的信息。

Gene flow occurs whenever two human populations come in contact. Thus, virtually all human populations are genetically dynamic, changing in their composition over time. The African-American population is the result of gene flow between two other identifiable biological groups: West Africans and American of European descent. This project will utilize dental characteristics to trace genetic relationship among these three groups. Characteristics of dental morphology, such as shovel-shaped incisors and Carabelli's trait, are useful for this purpose because they are highly heritable, do not remodel during life (although they can be lost to wear or pathology), and can be compared equally among samples from past and present populations. The results of this research will provide new knowledge about human microevolution in a biocultural setting. By analyzing a variety of samples from each biological group, observations will be made on patterns of genetic change through time and space. Additionally, by comparing the information from this study to other analyses of admixture in African Americans it will be possible to extend our knowledge of the history of the American population. Finally, the product of this study will include tables of dental trait frequencies in each of the three groups. This information is not currently available for African Americans and Americans of European descent.