For the first time, scientists have identified brain cells linked to depression

Published in Nature geneticsThe research provides new evidence that could guide the creation of treatments focused on these specific cells. It also advances scientific understanding of depression, a condition that affects more than 264 million people globally and is one of the leading causes of disability.

“This is the first time we have been able to identify specific types of brain cells that are affected by depression by mapping gene activity to the mechanisms that regulate the DNA code,” said lead researcher Dr. Gustavo Turecki, a professor at McGill University, a physician-scientist at the Douglas Institute and Canada Research Chair in Major Depressive Disorder and Suicide. “It gives us a much clearer picture of where the disorders occur, and what cells are involved.”

Rare brain bank enables breakthrough

The team conducted their work using post-mortem brain tissue from the Douglas-Bell Canadian Brain Bank, one of the few collections worldwide that includes donations from people with psychiatric conditions.

Through advanced single-cell genomic analysis, researchers examined RNA and DNA from thousands of individual brain cells to determine which behave differently in people with depression, and which DNA sequences might explain these differences. The study analyzed tissue from 59 individuals with depression and 41 people without it.

They discovered that gene activity was changed in two types of brain cells: a class of excitatory neurons responsible for regulating mood and stress, and a subtype of microglia, which are immune cells that manage inflammation in the brain. In both types of cells, many genes were differentially expressed in people with depression, suggesting possible disturbances in vital neural systems.

By identifying the specific cells affected, the research deepens understanding of the biological basis of depression and helps dispel outdated views about the condition.

“This research reinforces what neuroscience has been telling us for years,” Turecki said. “Depression is not just emotional, it reflects real, measurable changes in the brain.”

Looking to the future, scientists intend to explore how these cellular changes affect brain function and whether targeting them could lead to more effective treatments.

About the study

“Identifying mononucleosomal chromatin accessibility identifies cell types and functional variants that contribute to major depression” by Anjali Chawla, Gustavo Turecki, et al., published in Nature genetics.

The study was funded by the Canadian Institutes of Health Research, Brain Canada, Fonds de recherche du Québec – Santé and Healthy Brains, and the Healthy Living Initiative at McGill University.