Depression is incredibly complex, highly individual and most often linked to a cache of other triggers and comorbidities. But in 2021, a look at 1.2 million people found 178 gene variants linked to major depressive disorder (MDD) and confirmed that our DNA plays a key role in mental illness.
Now, researchers from McGill University, Canada, have made the case for more sex-dependent diagnosis models and treatment, after finding distinctly different genetic links for depression between male and female genomes.
In a study of more than 270,000 individuals taken from the UK Biobank database, scientists found that sex-specific prediction methods were far more accurate at assessing MDD risk than looking at the sexes together. They found 11 areas of DNA specifically linked to depression in females, and just one in the male genomes.
They also found that depression was acutely linked to metabolic diseases in females, yet previous research on this connection has been confirmed but not sex-specific.
Interestingly, the study found that both males and females shared issues with the BMAL1 protein, a regulator of circadian rhythms. Insomnia was one significant symptom both sexes shared when it came to MDD.
"This is the first study to describe sex-specific genetic variants associated with depression, which is a very prevalent disease in both males and females,” said Dr Patricia Pelufo Silveira, lead author and associate professor in the Department of Psychiatry at McGill University. “These findings are important to inform the development of specific therapies that will benefit both men and women while accounting for their differences.”
Among its complexities is the fact that depression varies so much in severity, symptoms and episode patterns, however, it’s estimated around 280 million across the globe suffer from it, and it’s largely responsible for the approximately 700,000 suicide deaths each year.
“In the clinic, the presentation of depression is very different for men and women, as well as their response to treatment, but we have very little understanding of why this happens at the moment,” added Dr Silveira.
The researchers hope this finding will lead to the development of tailored therapeutic options that can focus on sex-specific gene networks, and also encourage more scientists to investigate genomic cues for depression across racially diverse populations.
The study was published in the journal Molecular Psychology.
Source: McGill University