Grant: Doctoral Award - Frederick Banting and Charles Best Canada Graduate Scholarships

It is well known that early life adversity is associated with a variety of negative psychological outcomes ranging from depression to learning disabilities. However, what is not clear is the biological mechanism by which early adversity leads to changes in brain development that underlie these negative outcomes. Recently, researchers have turned to epigenetics as a potential explanation for this relationship. In particularly, it is believed that early adversity may induce chemical changes to DNA in a process known as DNA methylation, which may alter the outcome of various genes associated with brain development and function. For my thesis, I will study the relationship between DNA methylation, early adversity, and the brain. For the first part of my thesis, I will explore the association between brain development measures and DNA methylation in a well-documented longitudinal sample of genetically identical twins. Because twins share the same DNA, any differences between them in DNA methylation must be due to environmental factors, and not genetic differences. Thus, they present a unique opportunity to study the role of DNA methylation in brain development. For the second part of my thesis I will extend my findings from the first section to a sample using PET imaging techniques to examine the brain chemistry (i.e., serotonin) in individuals exposed to early adversity. I will also collect methylation data which will allow me to determine the utility of methylation as a marker of clinical problems associated with adversity. Together, these studies will allow me both to make well founded suggestions about the role of DNA methylation in early trauma and brain development. The findings of this study will help clarify crucial questions about how adversity affects mental health and may suggest and inform novel targets of intervention that may be valuable in treating mental health disorders.