Evolutionary Genetic Approaches to Dental Anthropology

人类和其他灵长类动物有复杂的齿系，包括各种数量，类型，形状和大小的牙齿。 生物发展的基本性质中的一个重要问题是了解这些结构如何产生的遗传基础。 从伦理上讲，我们不能直接对灵长类动物进行研究，因为关键的发育事件发生在胚胎中。 然而，这个问题可以在实验室小鼠中进行研究。 我们和其他人已经确定了在小鼠牙齿发育中表达的基因，并将使用各种实验方法来验证这些基因，以确定它们在这一过程中的作用。 此外，我们将采用现代DNA测序方法（称为EST识别）来寻找在发育中的门牙或臼齿（但不是两者）中表达的基因，因此可能有助于确定牙齿类型。 这些基因在发育中的牙胚中的表达将被表征。 因为老鼠的牙列不完整，我们不能将它们的发现自动翻译给人类或相关的灵长类动物。 然而，我们将在实验室负鼠中观察相同基因的表达，负鼠确实有一个完整的牙列，类似于人类和其他灵长类动物，以确定牙齿图案中的恒定元素，然后我们可以以各种方式在人类中进行研究（不是本项目的一部分）。 总的来说，我们希望这项工作将有助于了解牙列或其他类似的复杂特征是如何在胚胎中产生的，以及它们在物种之间是如何变化的。

Humans and other primates have complex dentitions, consisting of teeth of various numbers, types, shapes, and sizes. An important problem in the basic nature of biological development, is to understand the genetic basis for how such structures are produced. We cannot ethically work directly on primates because the critical developmental events take place in the embryo. However, this problem can be studied in the laboratory mouse. We and others have identified genes that are expressed in developing mouse teeth, and will use various experimental methods to inactivate these genes to determine their role in the process. In addition, we will be taking a modern DNA sequencing approach (called EST identification), to find genes that are expressed in developing incisors or molars, but not both, and hence may help determine the type of tooth. The expression of these genes in developing tooth germs will be characterized. Because mice have incomplete dentitions we cannot translate findings in them automatically to humans or related primates. However, we will be looking at the expression of the same genes in the laboratory possum, which does have a complete dentition, similar to humans and other primates, to identify constant elements in dental patterning which we might then study in humans in various ways (not part of this project). Generally, we expect this work will lead to an understanding of how the dentition, or other similarly complex traits, are produced in an embryo and how they vary among species.