1st Place Global Finalist, SARC 2026

Research Problem and Introduction:

Depression is a common mental disorder that affects people’s mood, thinking, and behavior, and

it continues to be a growing global health issue. One of the strongest risk factors identified for

depression is exposure to trauma, such as abuse or loss. However, not everyone who experiences

trauma develops depression. Some individuals remain resilient, which suggests that there are

could be certain biological differences that affect how people respond to trauma, not only

environmental factors. Recent research shows that depression is influenced by many genes rather

than a single one, making it a polygenic disorder (“Depression”). Scientists use polygenic risk

scores to estimate a person’s genetic risk by combining the effects of many genetic variants.

However, polygenic risk scores alone does not strongly predict whether someone will develop

depression, which suggests that environmental factors like trauma also play an important role

("Polygenic Risk"). In addition, biological systems related to stress and memory, such as those

involved in how the brain processes traumatic experiences, may affect whether someone

becomes depressed or stays resilient. Despite this, there is still limited research that combines

genetic risk, trauma exposure, and changes in symptoms over time to better understand

resilience. This study aims to find whether polygenic risk scores can help predict who develops

depression after trauma and how genetic risk interacts with trauma severity over time.

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Literature Review:

Previous studies have confirmed that depression is affected by many genetic factors, supporting

the use of polygenic risk scores (“Depression”). However, these scores on their own have limited

ability to predict depression, meaning other factors must be considered. Trauma is one of the

most significant environmental risk factors for depression. Research shows that individuals who

experience trauma, especially early in life, are more likely to develop depression

(Bany-Mohammed et al.). However, many people exposed to trauma do not develop depression,

which highlights the importance of resilience. Studies on gene-environment interaction show that

genetic risk can become stronger when combined with trauma. For example, research has found

that individuals with higher genetic risk are more likely to develop depression when they have

also experienced stressful or traumatic events ("Polygenic Risk"). Research on post-traumatic

stress disorder provides further support for this idea. A large study found that both polygenic risk

and trauma severity independently predict how symptoms change over time, with higher genetic

risk linked to worsening symptoms years after trauma (Mann et al.). This suggests that looking at

symptom trajectories, rather than just whether someone develops a disorder, provides a more

accurate understanding of resilience. Even with these findings, few studies combine polygenic

risk, trauma severity, and long-term symptom changes in depression. This gap is what the current

study aims to address.

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Research Question:

Can polygenic risk scores for depression predict whether an individual will develop depression

after trauma exposure, and how does trauma severity influence this relationship over time?

 

Methodology:​ 

This study will use a quantitative research design based on the analysis of existing genetic and

mental health data. The participants will include individuals who have experienced trauma and

have available genetic data. If possible, datasets with multiple measurements over time will be

used to track changes in depressive symptoms. The independent variable will be the polygenic

risk scores for depression; the dependent variable will be depression diagnosis and severity; and

an additional variable will be trauma exposure severity.The procedure involves individuals being

grouped based on trauma exposure and level of polygenic risk for depression, and their

depressive symptoms will be tracked over time, where longitudinal data is available The study

will then compare how depression develops and changes across these groups to determine

whether genetic risk and trauma severity predict differences in symptom trajectories. This study

will analyze how depression symptoms change over time. This allows for a better understanding

of resilience rather than just whether someone develops depression or not. The study will use

mixed-effects regression models to examine how depression symptoms change over time. This

type of analysis allows researchers to look at both the starting levels of depression symptoms and

how the symptoms will increase and decrease over time. Polygenic risk scores and trauma

severity will be used to predict these patterns. The study will also test whether trauma

strengthens the effect of genetic risk. This approach is supported by longitudinal research

showing that genetic risk and trauma severity can independently predict both initial symptom

levels and long-term changes over time (Mann et al.). The analysis will control for factors such

as age and gender to make the results more accurate. All data used in this study will be

anonymized to protect participant privacy, and the research will follow ethical guidelines for

genetic data use (American Psychiatric Association).

 

Conclusion and Feasibility:

This study aims to further understand how genetic risk and trauma work together to influence

depression. By using polygenic risk scores and analyzing symptom changes over time, the

research focuses on predictions as well as one’s reaction to trauma over time. The study is

realistic because it uses existing datasets and established statistical methods rather than requiring

new data collection or laboratory experiments. If successful, the results could help identify

people who are at higher risk of depression after trauma and personalize their treatment, as well

as support them earlier by providing therapy and counseling. Overall, this research could

improve understanding of how genetics and life experiences interact, helping researchers and

clinicians better predict depression, prevent depression, and help people with depression.

 

References :

American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders.

American Psychiatric Association, 2013,

https://doi.org/10.1176/appi.books.9780890425596. Accessed 29 Apr. 2026.

Bany-Mohammed, Mo'men, et al. "Trauma, Stress, and Mental Health Outcomes." Journal of

Psychiatry and Psychiatric Disorders, vol. 9, no. 5, 2025,

https://doi.org/10.26502/jppd.2572-519x0260. Accessed 29 Apr. 2026.

"Depression." MedlinePlus, medlineplus.gov/genetics/condition/depression/. Accessed 29 Apr.

2026.

Mann, Frank D., et al. "Polygenic Risk and Exposure Severity Predict Trajectories of PTSD: A

Prospective Cohort Study." Molecular Psychiatry, vol. 31, no. 1, 19 Sept. 2025, pp.

39-47, https://doi.org/10.1038/s41380-025-03235-2. Accessed 29 Apr. 2026.

"Polygenic Risk Scores." National Human Genome Research Institute,

www.genome.gov/Health/Genomics-and-Medicine/Polygenic-risk-scores. Accessed 29

Apr. 2026.