directed by Dr. Cecil M. Lewis

 

 

 

 

Welcome  

 

The University of Oklahoma's Molecular Anthropology Laboratories is active in quantitative population genetics, ancient and contemporary DNA research and field research in South America. We address questions concerning human population history, the evolution of disease associated genetic variation, and the relationship between cultural, environmental and genetic variation.

Related Resources

The University of Oklahoma's Anthropology Department has 25 full time faculty. Resources and programs such as Archaeological Survey, Native American Languages, and Native American Studies provide additional faculty and staff.

The Molecular Anthropology Modern and Ancient DNA Labs are housed in the Stephenson Research and Technology Center (SRTC). The SRTC includes labs and offices for several of our faculty and students.

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Director's Academic Areas of Interest

Disease associated genetic variation

Human population history

Recent projects and their practical importance

As a specialist in molecular population genetics, my projects cover a wide range of topics, from ancient microbial ecologies to prehistoric human migrations to the molecular evolution of genes involved in metabolism. Importantly, these topics are connected. For example, from a population genetics methodology, in order to assess whether natural selection has recently influenced genes involved in metabolism one must first consider what is expected of those genes evolving without such selective pressures. This baseline is drawn from an understanding of the population's history. Consequently, my work on human population history forms a necessary foundation for my work on the evolution of human metabolism. Similarly, metabolism in humans is not simply dictated by human genes. Microbes in the human gut are known to assist in human digestion, improve energy intake, produce vitamins and even help in the development of a healthy immune system. Here my research on ancient human microbiomes complements my work on the evolution of metabolism-related genes. All of these projects are further connected by similar wet-lab and analytical methods.

Ancient human microbiomes: link

My colleagues and I recently conducted a detailed analysis of two extinct human microbiomes. Microbiomes are the collective genomes of a microbial ecosystem. A human microbiome refers to those microbial ecosystems living on or in humans. Human microbiomes are a very important subject of scientific research today. Such microbial ecologies are known to influence human health. Because of the use of antibiotics, probiotics, and the general global economy, human microbiomes today may be fundamentally different from those that co-adapted with our ancestors. The study of ancient human microbiomes provides a view of these ecosystem prior to the modern human condition.

Human population history: link, link, link

My research frequently uses molecular genetic data to evaluate population history. Recently, my colleagues and I published the largest genome-wide survey of genetic markers for Native American communities. These studies are more than just aesthetic in value. They determine how much and what types of genetic variation can be found in different regions of the world - known as "geographic structure". This is important information for predicting and preventing diseases influenced by genes. To give one example, consider a genetic study that reveals that a particular population has recently declined in size, and as a consequence, has lost much of its genetic variation. In addition to the loss of variation, these "bottleneck" events result in dramatic changes in the frequencies of certain gene types. These types or "alleles" can be those the provide a special resistance or susceptibility to disease. As noted earlier, these population history studies also provide a foundation for more detailed studies of human evolution. Human evolution studies have further practical importance.

Recent molecular evolution in human populations: link

My colleagues and I published an analysis of a gene named OPN1LW, which is an important gene for color vision. Our study suggest that sometime after humans separated from their common ancestor with chimps (within the last 6 million years) Natural Selection began to have a very strong role in shaping the variation of OPN1LW in humans. From this study, we can see clearly that color vision was important to our ancestor's survival. While many of us are driven to better understand our human heritage, these types of evolutionary studies have other important contributions.

By definition, studies of Natural Selection are evolution-based studies of health. Natural Selection describes a process in which the environment and genes interact to influence an individual's ability to produce healthy offspring. For example, we are examining genes involved in the metabolism fatty acids and nicotine. These genes have alleles that are associated with risks and resistance to diseases such as diabetes and lung cancer. Our goal is to reveal the origins of these alleles and to help to determine the risks of diseases for certain populations. The genetic variation of these genes is geographically structured, maybe because of population history or maybe because the alleles have different health effects in different environments. Our evolution studies consider these different hypotheses and determine which best fits the genetic data.