Research has found that the risk for developing OCD is not only due to the genes we inherit from our parents, but also from environmental factors. However, it is unclear precisely which factors increase this risk, and by how much. By exploring how genetic and environmental factors interact further, it may be possible to ultimately diagnose and treat OCD earlier and faster.
Dr. Mataix-Cols and his team recruited 49 identical twin pairs (who share the same exact genes) where one twin has OCD and one does not – with the goal of understanding whether something in the environment led to OCD developing. The team accessed a vast amount of early-life and medical information about these twin pairs using the unique Swedish nationwide registries. They also built a database of biological samples from each participant, including samples that were taken at birth for the Swedish phenylketonuria (PKU) screening biobank. The team analyzed this data to identify the environmental variables that increase risk for developing OCD. This research project could unlock new information about why certain people develop OCD, and even lead to knowledge that would allow us to prevent OCD from taking hold in the first place.
Preliminary findings show that infections, childhood bullying, and exposure to interpersonal trauma are associated with an increased risk of developing OCD in twins who have it compared to twins who do not. However, not all traumatic events were associated with OCD risk, and that childhood bullying and OCD risk was not strongly associated with a genetic cause, indicating a complex relationship between genetics and environment.
The study has received additional funding outside the IOCDF to continue its progress.
Resulting Publications:
Mataix-Cols, D., de la Cruz, L. F., de Schipper, E., Kuja-Halkola, R., Bulik, C. M., Crowley, J. J., Neufeld, J., Rück, C., Tammimies, K., Lichtenstein, P., Bölte, S., & Beucke, J. C. (2023). In search of environmental risk factors for obsessive-compulsive disorder: Study protocol for the OCDTWIN project. BMC Psychiatry, 23(1):442.
Mataix-Cols, D., Fernández de la Cruz, L., Beucke, J. C., De Schipper, E., Kuja-Halkola, R., Lichtenstein, P., & Pol-Fuster, J. (2024). Heritability of Clinically Diagnosed Obsessive-Compulsive Disorder Among Twins. JAMA Psychiatry, 81(6), 631–632. https://doi.org/10.1001/jamapsychiatry.2024.0299
Pol-Fuster, J., Kuja-Halkola, R., Fernández de la Cruz, L., Brikell, I., Chang, Z., D’Onofrio, B. M., Larsson, H., Lichtenstein, P., Beucke, J. C., De Schipper, E., & Mataix-Cols, D. (2024). Association between severe childhood infections and subsequent risk of OCD is largely explained by shared familial factors. BMJ Mental Health, 27(1), e301203. https://doi.org/10.1136/bmjment-2024-301203
Pol-Fuster, J., Fernández de la Cruz, L., Beucke, J. C., Hesselmark, E., Crowley, J. J., de Schipper, E., Brikell, I., Chang, Z., D’Onofrio, B. M., Larsson, H., Lichtenstein, P., Kuja-Halkola, R., & Mataix-Cols, D. (2025). A Population-Based Multigenerational Family Coaggregation Study of Severe Infections and Obsessive-Compulsive Disorder. Biological Psychiatry, 97(7), 672–677. https://doi.org/10.1016/j.biopsych.2024.09.004
Pol-Fuster, J., Fernández de la Cruz, L., Isomura, K., Sidorchuk, A., Kuja-Halkola, R., Lichtenstein, P., D’Onofrio, B. M., Brikell, I., Larsson, H., de Schipper, E., Beucke, J. C., & Mataix-Cols, D. (2025). Association between bullying victimization and obsessive-compulsive disorder: a population-based, genetically informative study. Molecular Psychiatry, 30(6), 2457–2462. https://doi.org/10.1038/s41380-024-02849-2
Pol-Fuster, J., Fernández de la Cruz, L., Kuja-Halkola, R., De Schipper, E., Lichtenstein, P., Chang, Z., Brikell, I., D’Onofrio, B.M., Larsson, H., Rück, C., Brander, G., Beucke, J.C., Valdimarsdóttir, U.A., & Mataix-Cols, D. (2026). Short-and long-term incidence of obsessive-compulsive disorder after objectively recorded potentially traumatic events. Nature Mental Health, in press.