Depression is one of the most common mental health disorders in the world, but its underlying causes are still not fully understood. In a recent article from The Guardian, science correspondent Anna Bawden reports on a new large-scale study that significantly advances our understanding of the genetic basis of depression. The researchers, part of an international team, conducted a genome-wide association study (GWAS) using genetic data from over 1.3 million people. They discovered more than 250 additional genetic variants that may influence a person’s risk of developing depression. This more than doubles the number of previously known risk factors and provides new clues about how depression might be rooted in biological processes within the brain.

The article explains that many of these variants are found in regions of the genome related to brain cell communication and the regulation of neurotransmitters, which are chemicals that affect mood and behavior. Some variants are linked to genes that help brain cells signal each other, particularly in regions involved in decision-making and emotional regulation. The researchers suggest that identifying these genes could one day help create more targeted treatments or preventive strategies for people who are at higher genetic risk. The article emphasizes that while these genetic variants can increase susceptibility, they are not a guarantee that someone will develop depression, as environment and lifestyle still play important roles.

This article is directly related to genetics because it focuses on how small changes in DNA—called genetic variants—can collectively contribute to the likelihood of developing a complex condition like depression. These variants are typically single nucleotide polymorphisms (SNPs), which are tiny differences in the genetic code. Since each variant only has a small effect, scientists need large data sets to detect patterns. That’s why studies like this one rely on huge sample sizes and international collaboration. GWAS has become one of the most important tools in modern genetics for studying complex traits influenced by multiple genes.

To support the accuracy of the article, I reviewed a scientific paper published in Nature Neuroscience by Howard et al. (2019). This study also conducted a large-scale GWAS involving over 800,000 individuals and identified 102 genetic variants associated with depression. Like the newer study discussed in the Guardian article, the Howard et al. paper confirmed that depression is highly polygenic, meaning that many different genetic variants each contribute a small amount to the overall risk. It also highlighted the importance of specific brain regions, like the prefrontal cortex, in mood regulation and susceptibility to depression. These findings align well with the claims made in the article, showing that the popular press report is based on solid scientific evidence, even though it simplifies the details for a general audience.

Together, the Guardian article and the Nature review highlight how genetics is helping scientists make real progress in understanding mental health. By identifying more genetic risk factors, researchers are moving closer to uncovering how depression works on a molecular level. This could eventually lead to more personalized treatment options, based not only on symptoms but also on a person’s genetic profile.

Works Cited

Bawden, A. (2025, January 14). Scientists find hundreds more genetic risk factors for depression. The Guardian. https://www.theguardian.com/society/2025/jan/14/scientists-find-hundreds-more-genetic-risk-factors-for-depression 

Howard, D. M., Adams, M. J., Clarke, T.-K. et al. Genome-wide meta-analysis of depression identifies 102 independent variants and highlights the importance of the prefrontal brain regions. Nat. Neurosci. 22, 343–352 (2019).