I  hold joint appointments as a Group Leader in the MRC Human Genetics Unit in the MRC Institute of Genetics and Molecular Medicine and as a Principal Investigator in the Roslin Institute, both these organisations being part of the University of Edinburgh. My research interests lie in developing an understanding of the control complex traits, where inter-individual variation within and between populations is controlled by variation at a number of genes (often referred to as quantitative trait loci or QTL), by environmental factors and by the complex interactions of these components. Most variation between individuals within and between populations is in the form of complex traits. Consequently variation in complex traits is responsible for most inter-individual variation in susceptibility to disease (both infectious and metabolic) in humans, livestock and other species and underlies responses to selection, both artificial selection in livestock and natural selection in all species. We can only be really effective in understanding and treating many diseases, in predicting individual’s risk of developing particular conditions and in dissecting the causes and consequences of natural selection if we understand the genetic control of variation in complex traits.

My research focuses both on developing approaches to dissect complex traits and in applications of these approaches to specific biological models. My group has developed the most widely used approaches for linkage mapping of QTLs livestock. These were made available to the community the through the software QTL Express and latterly through GridQTL. We have further developed and applied methods for the analysis of the high density of markers that are available in human populations and which are becoming available in various livestock breeds and developed, disseminated and applied analysis methods for detection of gene interactions (epistasis). I have has led and collaborated in a large number of projects focusing on the dissection of complex traits in a range of species. These have included the first genome-wide scan of QTLs in livestock and many subsequent studies as well as studies in humans, fish, model vertebrates and plant species. Current research includes focus on the use of genomic information to predict individual’s complex trait phenotypes and health outcomes, the development and application of statistical approaches to capture rare variants, epistatic variation and other genetic variation that escapes standard genome-wide association analysis and understanding and utilizing the genomic causes of complex trait variation.

Understanding complex trait variation in humans and other species.

My interested is in developing an understanding the control of complex traits, where inter-individual variation within and between populations is controlled by variation at a number of genes, by environmental factors and by the complex interactions of these components. Most variation between individuals within and between populations is in the form of complex traits. Consequently variation in complex traits is responsible for most inter-individual variation in susceptibility to disease (both infectious and metabolic) and underlies responses to selection, both natural and artificial. Understanding the genetic architecture of complex traits, both in general and for specific traits in particular populations, is essential if we are to understand why and how individuals vary. We can only be really effective in understanding and treating many diseases, in dissecting the causes and consequences of evolution or in breeding improved varieties of plants or animals if we understand the genetic control of variation in complex traits.

My research focuses on studies of the control of complex traits illustrated by results from specific examples. My group has been involved the development of specific experimental studies and the resources necessary to implement these studies together with the development and application of methods and tools capable of analysing and interpreting the data generated by my group and our collaborators. In recent years research has focused on the development and application of statistical methods in particular for mapping the position of individual loci affecting quantitative traits (quantitative trait loci or QTL) through linkage and association in humans and other species. The tools of structural and functional genomics have now reached a point where we can identify genes controlling variation with ever increasing precision, we can dissect interactions between genes and not just their direct effects and we can start piecing together the complex networks of interactions in expression and function that lie between genes and the phenotypes. These are the directions in which my current and future research lies.
  

I have been teaching on MSc courses at the University of Edinburgh for more than 25 years. I was involved in the reorganisation of the MSc in Animal Breeding which became the MSc in “Quantitative Genetics and Genome Analysis” in 2000. This reorganisation expanded teaching of quantitative genetics from animal breeding to unite the areas of quantitative genetics applied to human, livestock and natural populations. Since the launch of the new MSc I have sat on the examination board of the MSc as representative of the Roslin Institute since then. With Sara Knott I co-organise the “Linkage and Genome Analysis” section of the course and teach over a period of three weeks on this course. I also supervise summer MSc research projects.

I have both organised and taught on international post-graduate courses on livestock genomics and run international courses on QTL analysis 

I am interested in understanding why individuals vary one from the other. Most characteristics, whether it is in a population of humans or of farm animals, vary from individual to individual. Some are taller, some shorter; some are quick growing and some slow growing; some are more susceptible to disease and some more resistant. Variation in such characteristics is usually controlled by many different genes combined with environmental factors such as diet and upbringing. However, for most characteristics we know very little about the genes that are involved or how they act to influence an individual’s growth, strength and health. Therefore, my research involves analysing variation of characteristics in large populations of animals or humans and attempting to identify the genes that may contribute to this variation. An improved knowledge of how genes act to control variation between individuals could be valuable in a number of ways. For example an understanding of the biology would help in the design of drugs to combat disease in humans and livestock and knowledge of the genes involved could help select cows that have naturally more efficient milk production.