Searching for Genetic Biomarkers of OCD

Treatment of (Obsessive-Compulsive Disorder) OCD, mood and anxiety disorders usually involves a trial-and-error process as physicians search for the medications that will have the best results (i.e., good response and least side effects) for their patients. But what if there is a way to determine the best medication for a patient without a long and uncomfortable period of experimentation?

Dr. Gwyneth Zai is an Assistant Professor in the Department of Psychiatry and a Clinician Scientist and Staff Psychiatrist at CAMH. Her research explores biomarkers – biological signs that can indicate the presence or potential for mental illness before symptoms fully emerge. She has performed research on a variety of disorders, including ADHD, mood disorders, and schizophrenia, and over the past several years, she switched her focus on OCD, mood and anxiety disorders.

Currently, it usually takes physicians treating patients with OCD several trials to find the right medication for a particular patient. Individuals respond differently to medications. For example, a particular drug with a specific dosage may help one individual manage their symptoms, but the same treatment may have no effect or even make symptoms worse in another patient. Trying different drugs is expensive and can be very difficult for the patient. However, without a better understanding of the etiology of OCD, it can be difficult to avoid. Unfortunately, research into OCD has been comparatively limited, lagging behind research work in mood disorders and schizophrenia for example.

“There are lots of misconceptions about OCD,” says Zai, “It can be very debilitating. Compared with other disorders, there’s not as much research happening in OCD.”

Zai is exploring the possibility of using a patient’s DNA to predict their response to medications. Almost all psychiatric disorders are complex and present differently from patient to patient, and most psychiatric disorders have associated cognitive deficits, a decrease in the patient’s cognitive abilities. Dr. Zai hopes to identify the genetic markers that are responsible for those deficits. If she can identify specific genetic factors that are associated with a specific cognitive deficits, these genetic markers can potentially be used to predict what treatments patients will be responsive to.

Zai’s passion in genetics has a long history, going back to the explosion of interest in the interaction between DNA and environmental factors after the discovery of epigenetics. Her interest in the field only grew, continuously through her undergraduate and MD training. The Psychiatry Department’s strong research programs appealed to her, and her current work provide an opportunity for her to continue her clinical interest in the mood and anxiety population and her research focus on biomarkers in the same patient population.

Zai’s research was given a major boost when she received support from the Labatt Family Innovation Fund in Brain Health in 2018. As she continues he work, she remains focused on the positive impact it could have in patients.

 “If we can tailor medications to each patient based on biomarkers, we can avoid the traditional trial-and-error process,” says Zai, “This will greatly reduce the suffering that patients must go through.”