The Human Genome Project and Advances in Anthropological Genetics

Keywords
Human Genome Project, anthropological genetics, Human Biology journal, editorial.

Anthropological genetics is at one of the most exciting points in the history of the field. Never before has so much information been available to facilitate the search for genes that influence normal human variation and human adaptability. For example, sequencing efforts have revealed vast amounts of variation within human populations. The Human Genome Project has opened a new frontier in anthropological genetics, and we can look forward to a time of rapid progress in characterizing the genetic components of human variation.

After one year as the editor of Human Biology, I am well aware of the growing excitement in the field of anthropological genetics. At a time when genes influencing disease-related phenotypes are being localized and characterized at an unprecedented rate, so too is dramatic progress being made in elucidating the genetic determinants of normal variation in the phenotypic traits that have traditionally been of interest in anthropology. With its extensive history of publishing research in anthropological genetics, Human Biology is well placed to be the journal where the latest developments in gene localization and identification of traits of anthropological relevance are published.

The data generated through the Human Genome Project have provided a rich resource of information that can be exploited in the search for genes influencing traits of relevance to anthropology. It is now possible for the first time to identify the specific genes that influence normal human variation and human adaptability on a large scale. We are poised to make great strides in improving our understanding of human microevolution through increased understanding of the genetic determinants of normal variation. The exciting growth in research on human populations, particularly in the areas of genomic screening and large-scale family studies, is yielding a wealth of new information about the determinants of variation in both normal and disease-related phenotypes. Genome scans not only allow unambiguous identification of genetic influences on human variation but also provide a means by which the environmental influences on human variation can be quantified and distinguished from genetic influences.

New analytical tools available for genetic analysis, such as variance components based linkage analysis [e.g., Almasy and Blangero (1998)], allow for the dissection of environmental and genetic contributions to phenotypic traits, including the localization and ultimate identification of the underlying quantitative trait loci. These approaches allow explicit incorporation of measured environmental effects so that the variance in a trait can be partitioned between genetic and environmental effects, for example, among genetic effects, household effects, sex effects, and random environmental effects. Similarly, these methods enable the assessment of the role of genotype-by-environment interaction in human variation. The study of genotype-by-environment interaction is of direct relevance to the field of human adaptability because it implies genetically based differential response to environmental challenge.

Over the next decade we can expect an explosive growth of research on the genetic determinants of phenotypic variation, particularly in the area of analyses of linkage between quantitative traits and specific genetic markers. Anthropological populations have unique advantages for many of these types of studies, and there is great interest in focusing on isolate populations for gene mapping. Although some studies have focused on true geographic isolates, such as the Icelandic population (Styrkarsdottir et al. 2003), others have utilized local populations that tend to be endogamous, such as the Mexican American population of San Antonio (Mitchell et al. 1996; Comuzzie et al. 2003; Arya et al. 2004) and the Jirel ethnic group of Nepal (Williams-Blangero et al. 1999, 2002).

The analysis of large extended pedigrees is a powerful study design for human genetic research designed to localize genes influencing human quantitative variation. Large extended pedigrees can be reconstructed in any stable population that has a relatively low migration rate. House-to-house sampling has been used to reconstruct extended pedigrees consisting of hundreds...