The focus of my research is on gene identification for complex traits and the determination of how DNA changes influence gene function and contribute to risk. My early work focused on determining how specific genes in the immune system were regulated. However, for the past 23 years, my work has been on the genetics of behaviour, specific aspects of cognition, and psychiatric and neurological disorders including attention-deficit hyperactivity disorder (ADHD), childhood-onset anxiety disorders, childhood-onset depression, reading disabilities (developmental dyslexia), and Tourette syndrome. Large genetic studies for these traits have been successful in identifying the position of genes contributing to these disorders and many of the identified genes overlap indicating shared genetic susceptibility across disorders. Interestingly, some of the genes implicated in psychiatric disorders are involved in the immune system. The results from the genetic studies provide overwhelming evidence that changes in gene expression are indicated for disease susceptibility for complex traits, and further that genome-wide association studies implicate genetic variation in specific types of regulatory element, enhancers and super-enhancers, in genetic risk. We are currently preforming functional studies of gene regulatory regions in associated regions for disease using CRISPR/Cas9 editing of cells to study function and high-throughput methods to study the role of genetic variation in gene regulation.