Research on rare post-mortem brain tissue shows changes in gene activity, offering new insight into the biological basis of depression.

Researchers from McGill University and the Douglas Institute have discovered two distinct types of brain cells that show alterations in individuals with depression.

Their study, published in Nature Genetics, paves the way for potential treatments that directly target these cells while also advancing scientific understanding of depression, a major global health challenge affecting over 264 million people.

“This is the first time we’ve been able to identify what specific brain cell types are affected in depression by mapping gene activity together with mechanisms that regulate the DNA code,” said senior author Dr. Gustavo Turecki, a professor at McGill, clinician-scientist at the Douglas Institute and Canada Research Chair in Major Depressive Disorder and Suicide. “It gives us a much clearer picture of where disruptions are happening, and which cells are involved.”

Rare brain bank enables breakthrough
The team examined post-mortem brain tissue from the Douglas-Bell Canada Brain Bank, one of the rare global resources containing donated samples from individuals with psychiatric conditions.

Using single-cell genomic methods, they analyzed RNA and DNA from thousands of brain cells to determine which cell types functioned differently in depression and which DNA sequences might account for those changes. Their analysis included samples from 59 individuals with depression and 41 without the condition.