The Genetic Aspects of Cranio-facial Growth

Abstract

Publisher Summary The genetics of cranio-facial size, growth patterns, tooth formation, tooth morphology, and eruption have been investigated by various methods. Careful study has shown that few characteristics are because of single gene effects and many, such as supernumerary cusps, often treated as discrete variables, are in all probability quantitative. The amount of measurable and observable variability in the cranio-facial complex is great and much of it has a detectable genetic component. The historical beginnings of anthropological interest in the dentition and cranial and facial characteristics implanted conceptual orientations that are in serious need of re-evaluation with respect to their adaptive significance in human evolution. Similarly, certain traditions in the genetic interpretations of dental traits are also in need of re-evaluation. While there is little question that some dental variation is dependent upon simple genetic mechanisms, the bulk of the observed variation is probably polygenic and will require more application of different types of analysis than is possible by traditional pedigree methods. The dental traits that are genetically simple provide some of the most valuable traits for linkage studies, which is currently an almost untouched area. These simple traits and even the genetic and developmentally complex characteristics for which the embryology is known also provide extremely useful tools for the study of chromosomal aberrations. To accomplish any of these objectives, broadly based investigations will be needed in which specialists from different scientific disciplines can collaborate in dental studies.