Scientists have identified a pattern of gene activity present in some female survivors of childhood abuse that is associated with an elevated risk of depression.
"We know childhood abuse increases the risk of depression at the population level, but at the individual level it's much harder to predict who will actually develop the disorder," said senior author Patricia Silveira, professor in McGill's Department of Psychiatry and researcher at the Douglas Mental Health University Institute. "Our findings point to a biological mechanism that may help explain who is more at risk, at least in women."
This pattern was not observed in men, suggesting the biological pathways linking trauma to depression may differ by sex. Understanding these differences is an area of growing interest in mental health research, she added, particularly given the higher rates of depression among women.
Tracing depression risk in the brain
Drawing on data from thousands of people in the U.K. Biobank, including data about their childhood experiences, mental health and genetic information, the researchers examined a gene network involved in synaptic function, a process known to be disrupted in depression.
Results published in eBioMedicine, part of The Lancet Discovery Science, indicate that among women who experienced childhood abuse, one configuration of this gene network was linked to a higher risk of depression.
"Our findings suggest that depression risk is shaped by how genes involved in synaptic function respond to early-life experiences. That makes synaptic function a promising target for future research," said co-first author Carla Dalmaz, a visiting professor at the Douglas from the Universidade Federal do Rio Grande do Sul.
The work is part of a broader effort to identify genomic signatures associated with risk for the disorder, which affects an estimated about 11 per cent of Canadian adults over their lifetime.
"Depression is diagnosed primarily based on reported symptoms, and there are still no widely accepted biological tools in routine clinical practice to identify risk early," added co-first author Danusa Mar Arcego, a research associate at the Douglas. "Our findings bring us a step closer to understanding why some people may be more vulnerable, opening the door to earlier support and prevention strategies."
About the study
" Sex-specific interaction effects of Syntaxin 1A coexpression network and childhood trauma on adult depressive symptoms " by Danusa Mar Arcego, Carla Dalmaz, Patrícia P. Silveira and co-authors was published in eBioMedicine. Funding was provided by the JPB Foundation, Hope for Depression Research Foundation, Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES-BR through their visiting professorship program), Fonds de recherche du Québec and the Canadian Institutes of Health Research.
