August 17, 2021
Interview with Professor David Evans
Position: NHMRC Senior Research Fellow
Organisation: Institute for Molecular Bioscience, The University of Queensland
One-liner: Genetic researcher, number cruncher and disease gene mapper!
Many scientists are excited that knowing your genome may allow doctors to better predict whether you will be at risk of disease in later life.
Professor Evans, what university courses, degrees and just general opportunities would you pursue if you were finishing school today and beginning your career in statistical genetics now?
Jasminder, Caloundra SHS
Unfortunately, the first time around I didn’t know what I wanted to study and so took courses on everything ranging from Law to Psychology! If I had my time again, I would focus heavily on mathematics (majoring in statistics) and computer science with a smattering of biology and genetics. If you have strong skills and a degree in Maths and IT it will open many doors for you and give you career flexibility.
What would be the most challenging yet interesting project of all the projects that you have investigated? And why?
Lauren, Southport SHS, Gold Coast
It would be hard to go past the first Wellcome Trust Case Control Consortium that I was very lucky to be part of. This was one of the very first large-scale genome-wide association studies (in this case of twelve different diseases) and the first to successfully map genes underlying a range of diseases including diabetes, rheumatoid arthritis, Crohn’s disease and ankylosing spondylitis (a form of arthritis). I was lucky enough to lead the genetic analysis of ankylosing spondylitis that discovered a gene predisposing to this disease that’s pathway is now targeted by a drug and used to treat thousands of patients with the condition.
What type of technology do you use to assist you in your genetic research?
Grace, Moranbah SHS
Genetic studies in humans over the last 15 or so years have used “microarray” technologies. These are small devices about the size of your palm that enable us to genotype about 1 million genetic markers across a genome. This technology is slowly giving way to newer but more expensive sequencing-based technologies where we genotype the entire genome of an individual (about 3.3. billion base pairs).
Did you realise at the time that the International HapMap project would be so important and revolutionary for research?
STEM Girl Power
When I began my career, nobody had ever discovered a gene predisposing to a common complex disease and there was considerable (and often heated) debate in the scientific community about whether such discoveries were even possible! At the time I thought that the HapMap might facilitate the discovery of a few genes but nothing like the tens of thousands of disease predisposing genetic variants that we know about today. Indeed if you look across the history of Science I don’t think that there has ever been such a concentrated flurry of discoveries across so many different diseases as what we have witnessed in human genetics research in the last twenty years.
How do you explain the potential of the power of statistical genetics to help us solve health issues to people who don’t understand statistics?
STEM Girl Power
Fortunately, you don’t have to have an in-depth knowledge of maths/statistics to build an intuition as to why statistical genetics can help solve health problems. For example, much of my work involves genome-wide association studies where we genotype a group of cases (individuals with a particular disease) and a group of controls (healthy individuals) on hundreds of thousands of genetic markers across their genomes. If a particular genetic marker occurs more frequently in cases than in controls, then this tells us that the particular gene must play a role in the disease process. The wonderful thing about this method is that it is completely agnostic – you don’t need any prior knowledge about the disease for it to work, and that has been one of its major strengths –identifying genes and biological pathways that we had no idea previously were involved in disease.
Genetically – what’s the impact of being left-handed?
STEM Girl Power
Inter-individual variation in common complex traits is due to a mixture of genetic and environmental factors (for most traits, about 50% of each). Handedness is a very interesting trait in that it is mostly due to environmental factors, and genetics seems to play a relatively minor role. The genes that we have discovered that predispose individuals to be left-handed don’t seem to exert too many effects on other traits and seem to mostly affect the laterality of function in the brain.
How can we use statistical genetics in the future? Are there concerns about discrimination if people have genetic traits or diseases?
STEM Girl Power
Great question! Many scientists are excited that knowing your genome may allow doctors to better predict whether you will be at risk of disease in later life. We are still a little way off, but this is likely to be the case in the future, for at least some diseases. It is important therefore that politicians craft laws to prevent discrimination on the basis of this information.
Do you believe the research being undertaken for COVID-19 will benefit other fields of science and how?
Grace, Kirwan SHS, Townsville
Scientists in my field are using large scale genetic studies to identify genetic variants that predispose to more severe disease from COVID. This work has identified several genes whose protein products may become future targets for COVID therapy.
Where do you believe the future of science is heading and what potential is there?
Grace, Kirwan SHS, Townsville
That’s quite a broad question Grace (!), so I will limit my response to my particular area (genetics of common disease). In the next ten years, I think we will have a very good understanding of the genetic basis of most common diseases and understand many of the biological pathways underlying their pathophysiology. For a proportion of these diseases, the genetic discoveries will lead to new drug therapies, and for some of the more heritable conditions, we will be able to identify individuals who are at high risk of suffering from them in later life just by looking at their genome.
While Professor David Evans enjoyed learning about biology, he didn’t like working in wet labs. Then he found an opportunity in an emerging area of medical science – statistical genetics – that enabled him to use mathematics and computing to perform cutting edge genetic research without stepping into a laboratory.
Professor Evans uses mathematics and statistics to answer fundamental questions about the genetic and environmental causes of common diseases.
From 2003 to 2007, he worked on the International HapMap Project (a map of the human genome that facilitates the genetic mapping of diseases) at the University of Oxford and was part of The Wellcome Trust Case Control Consortium, one of the first large-scale genetic studies to look across the genome to identify individual genes that affect the risk of common diseases like diabetes and heart disease using statistical genetics approaches.
From 2007, at the University of Bristol, he led genetic studies within the Avon Longitudinal Study of Parents and Children (ALSPAC) - a population-based cohort of 10,000 mothers and children that is now one of the world’s leading cohorts for genetics research. ALSPAC has contributed to over forty large-scale genetic studies of medically relevant traits and diseases including osteoporosis and eczema, and has helped identify hundreds of genes that predispose to disease in the process.
Now based at the University of Queensland, Professor Evans leads several internationally based projects including studies investigating the genetic basis of low birthweights and studies aimed at understanding genetic and environmental aetiology of left-handedness. He is also very active in developing statistical methods to facilitate gene identification. He is hoping to find PhD students who are interested in pursuing closer links between Australia and the UK.