Doctoral Dissertation Research: Documenting differences in gene expression during human tooth development to understand the evolution of the primate dentition

University Of Florida, Gainesville FL

Investigators

Abstract

Primate species, including humans, have diverse dental patterns that reflect different dietary and ecological specializations, but the genetic mechanisms that underlie these differences are poorly understood. The goal of this study is to identify specific genes that are responsible for tooth formation and tooth shape in humans and other primates. The investigators will use human and mouse dental tissues in conjunction with state-of-the-art molecular techniques to identify genes and measure differences in gene expression across tooth types (i.e. incisors, canines, premolars). The findings from this novel and potentially transformative study will not only advance science by informing research on dental evolution, but may have societal impact by contributing to the understanding and future treatment of dental malformations in humans. In this 24 month study, cutting-edge RNA sequencing technology will be used to quantify levels of expression of all genes at a key stage in human tooth development (cap stage), and to compare dental gene expression in humans and mice. Identifying individual genes that are the primary determinants of a tooth's cusp pattern will help explain how the human dentition is patterned during development and what dental genes have been conserved during mammalian evolution. This research will result in novel, testable hypotheses of how differences in gene expression may produce dental variation and adaptations seen in extinct and extant primate species. This represents a first step towards understanding evolutionary transitions that gave rise to the present dental diversity among primates because the genetic and developmental drivers of changes in tooth shape cannot be uncovered until the formation of differently shaped teeth is fully characterized. In addition, knowledge of the genetic components required for tooth formation will provide potentially transformative new information on the genetic underpinnings of anatomical anomalies in teeth. The project will also provide student training and scientific outreach, including a guided-inquiry lab in which undergraduate students will test hypotheses of the correspondence between tooth morphology, function, and diet in mammals and learn how differently-shaped teeth develop.