The Neurogenetics Section focuses on identifying genetic factors involved in the development of mental illnesses and addictions. Our lab has one of the largest collections of DNA, with over 23,000 samples, which have been donated by individuals with common diagnoses such as schizophrenia and obsessive-compulsive disorder, as well as rarer afflictions such as body dysmorphic disorder.
One major discovery was of the remarkable genetic variation of the dopamine D4 receptor. Later we found that a variant of D4 is involved in attention deficit hyperactivity disorder (ADHD), a finding that has been extensively replicated. This work has prompted testing of D4-binding molecules (ligands) as a treatment for ADHD. D4 antagonists, molecules that block D4, have shown success in suppressing addictive behaviour. For obsessive-compulsive disorder (OCD), we discovered the role of the serotonin 1B gene and the glutamate transporter gene in causing OCD. The latter finding was issued a U.S. patent in 2008.
Another major area of research is pharmacogenetics. We are identifying variations in specific genes that lead to different responses to medication or to adverse side effects. Our lab has developed a genetic test of the serotonin transporter gene, which predicts a person’s risk of developing anti-depressant-induced mania. Building on discoveries around weight gain related to antipsychotic use, we are beginning to build a multi-gene predictive test for antipsychotic medication response and side effects.
Current projects
- an analysis of thousands of patients in the Tanenbaum Centre for Phamacogenetics to establish the clinical usefulness of pharmacogenetics in psychiatry, which aims to provide evidence supporting the idea of proactively testing patients before they start drug treatment to prevent side effects and treatment failure (co-investigators: Drs. Daniel Mueller and John Strauss)
- NeuroIMAGENE, an initiative using brain imaging and genetics to better understand mental illness and personalize treatment (Dr. Kennedy is co-PI with Dr. Sylvain Houle)
- genetic discoveries in schizophrenia examining genetic vulnerabilities regarding specific traits such as age of illness onset, number of affected members, marijuana use as a risk factor
- subphenotypes, deep sequencing and interactions, and genetic factors associated with treatment response
- analysis of genetic and epigenetic changes due to stress, medications and disease course in patients with bipolar disorder or schizophrenia, and identification of genes and neurotransmitters relevant to suicidal behaviour
Lab members
Head: Dr. James Kennedy
Scientists: Dr. Daniel Mueller, Dr. John Vincent, Dr. Jo Knight, Dr. Laurie Zawertailo, Dr. Vincenco De Luca, Dr. Daniela Lobo, Dr. Aristotle Voineskos (cross appointed to Research Imaging Centre)
Administrative Assistant: Andrea Smart
Lab Manager: Natalie Freeman