Article Impact Level: HIGH Data Quality: STRONG Summary of Nature Human Behaviour. https://doi.org/10.1038/s41562-025-02193-7 Dr. Elham Assary et al.
Points
- A large-scale twin study involving 21,792 identical twins revealed that genetic variants influence how individuals respond to environmental exposures related to psychiatric and neurodevelopmental traits.
- Genes involved in stress reactivity, growth factors, and catecholamine uptake were associated with increased sensitivity to depression, autistic traits, and psychotic experiences, respectively.
- The study emphasizes that genotype-by-environment interactions help explain why even genetically identical individuals can display different psychiatric outcomes when exposed to similar life circumstances.
- Researchers used a twin-based design to isolate environmental effects and found genetic contributions to sensitivity accounted for up to 18% of phenotypic variance across mental health traits.
- These findings support future research into personalized mental health strategies that consider individual genetic sensitivity to environmental stressors and psychiatric risk.
Summary
A recent international study by King’s College London explored the genetic factors contributing to individual sensitivity to environmental exposures and their impact on psychiatric and neurodevelopmental conditions. The research, published in Nature Human Behaviour, analyzed data from 21,792 monozygotic (identical) twins from 11 studies to identify genetic variants linked to varying sensitivity to environmental factors. These factors include ADHD symptoms, autistic traits, anxiety, depression, psychotic experiences, and neuroticism. The study found that genetic variants influenced the extent to which individuals were affected by their environments, contributing to differences in susceptibility to these conditions.
The study identified several significant genetic associations. Genes related to stress reactivity were linked to variations in depression symptoms, growth factor-related genes were associated with autistic traits and catecholamine uptake-related genes were tied to psychotic-like experiences. These findings suggest that genetic factors can shape how individuals respond to life experiences, influencing the expression of various psychiatric and neurodevelopmental traits. This work underscores the importance of genotype-by-environment interactions in mental health, offering new insights into why identical twins exposed to similar environments can exhibit different psychiatric outcomes.
The researchers used a family-based approach, taking advantage of the genetic similarities between monozygotic twins to isolate environmental influences. The study highlights the utility of this methodology in unraveling complex gene-environment interactions, particularly in understanding mental health conditions. Although the study found evidence of genetic contributions to environmental sensitivity, the precision of the findings was limited, with the proportions of phenotypic variance explained by these genes ranging from 0% to 18%. This study provides a framework for future investigations into the genetic basis of mental health, laying the groundwork for personalized interventions based on genetic susceptibility to environmental stressors.
Link to the article: https://www.nature.com/articles/s41562-025-02193-7
References Assary, E., Coleman, J. R. I., Hemani, G., Van De Weijer, M. P., Howe, L. J., Palviainen, T., Grasby, K. L., Ahlskog, R., Nygaard, M., Cheesman, R., Lim, K., Reynolds, C. A., Ordoñana, J. R., Colodro-Conde, L., Gordon, S., Madrid-Valero, J. J., Thalamuthu, A., Hottenga, J.-J., Mengel-From, J., … Keers, R. (2025). Genetics of monozygotic twins reveals the impact of environmental sensitivity on psychiatric and neurodevelopmental phenotypes. Nature Human Behaviour. https://doi.org/10.1038/s41562-025-02193-7
