I am a Reader in Psychology at the University of Edinburgh, having trained in Behavioural Genetics at the QIMR Berghofer Medical Research Institute in Brisbane, Australia (1999-2002). My research focuses on the genetic and environmental aetiology underlying human development and behaviour. One of my main research interests is to understand what causes the variation between people in how well they read and use language. And to do this, I use behavioural genetic research methods. This includes twin and extended pedigree designs, molecular genetic techniques, epigenetic, and gene x environment interaction modelling. Most recently, I have led an international collaboration which has discovered genes significantly associated with dyslexia.
How did you became interested in learning difficulties?
My PhD focussed on different types of cognitive abilities (like processing speed, memory, spatial ability) and how they relate to each other on a genetic and environmental level in adolescence. Learning, of course, is dependent on these abilities, and after my PhD, I began to focus especially on our ability to read and spell (i.e., learned skills). Here, I was interested primarily in the genetic underpinnings that explain why people vary in their ability to read and write. Genetic research on learning difficulties in reading and spelling (also known as dyslexia) was very relevant to my work because there was more known about the genetics of reading difficulties (historically termed as disorder or disability). But even more importantly, I hold the view that genes affecting poor reading operate across the entire distribution of reading skill, so understanding the causes of reading difficulties will also tell us about the causes of skilled reading. Because reading is essential to pretty much everything people do in the modern world, I’ve developed a special interest in the potential to raise literacy levels of people who have the greatest learning difficulties, and to this end, I am investigating whether knowledge of genetics can assist.
Can you give us an overview of your work?
I am interested in how cognitive abilities develop (including difficulties in learning cognitive skills) and how they change in old age. It is well established that genes explain some of the differences between individuals in their cognitive functioning. I use genetic methods like genome-wide association and family designs (twin and pedigree studies) to understand the genetic underpinnings of human variation in cognitive abilities. These focus on identifying specific genes associated with different cognitive abilities and the biological pathways and brain regions that are implicated in these associations. They also focus on understanding the genetic and environmental relationships between different types of cognitive abilities, the same cognitive ability over time, and relationships with socio-educational and health variables. Increasingly, my focus is turning to the interaction of genes and the environment, and here I am using polygenic scores (a composite score of 1000’s of small genetic effects that are associated with a trait) to understand how their association with reading changes in the presence of adverse environments.
What are the most pressing research priorities?
Because I am hopeful that genetic information can help us identify children who are more likely to experience a learning difficulty and the environmental conditions in which this risk is highest, I think a research priority around early intervention is needed. That is, establishing the age at which intervention works best, and the type of intervention that works best for children with varying genetic predisposition to learning difficulties. Around the topic of learning difficulties, I think it’s also vital to gather reliable evidence about the behavioural and mental health correlates of having a specific learning difficulty. Is more support needed to prevent learning difficulties becoming a barrier to socio-educational attainment and potentially good mental health?