May 14, 2025

Obsessive compulsive disorder has many unknowns, including what causes it, why symptoms can differ so much between people, how medication and therapy for it actually work, and why treatment is effective for some people and not for others. In our newly published research, my colleagues and I made a step toward unraveling some of these mysteries by shedding light on the genetics of OCD. Obsessive compulsive disorder is one of the most impairing illnesses worldwide. Affecting about 1 in 50 people globally, OCD is among the top 10 causes of years lost to disability, leading to harmful effects on a person’s ability to work and function in the world and on their family. Compared with people without OCD, a person with the condition has a 30% higher chance of dying prematurely from natural causes, such as infections or other illnesses, and a 300% higher chance of dying early from nonnatural causes, such as accidents or suicide. People with OCD experience obsessions – disturbing, recurrent and unwanted thoughts, fears or mental images – and compulsions, such as repetitive behaviors and rituals performed to ease the anxiety usually caused by obsessions. For example, someone might wash their hands dozens of times or in a specific way to get rid of germs, even if they know it’s excessive or illogical. Avoiding certain places or situations to reduce anxiety or prevent triggering obsessions and compulsions is also common.