Study: Men, women have opposite genetic alterations for depression

PITTSBURGH — Men and women diagnosed with major depressive disorder (MDD) experience opposite changes in the same gene, a recent study finds.

The findings, according to researchers, suggest that men and women should have different treatment for MDD. They’re also the first to show sex-specific differences in genetic and molecular changes in the disorder.

“While researchers have been examining the brains of depressed subjects for decades, many of these studies included only men,” says lead author Marianne Seney, PhD, of the University of Pittsburgh, in a release. And yet despite the lack of diversity in prior research, women are twice as likely to be diagnosed with MDD as men are, and often report different symptoms and greater severity of symptoms.

For the study, researchers combined eight published datasets, four for men and four for women, in a meta-analysis. The team then analyzed gene expression levels in the postmortem brain tissue of 50 people, 26 of whom were men. They compared these gene expression levels with that of unaffected men and women for comparison.

Most of the genes analyzed that showed an altered expression in patients were changed in only men or only women. But these altered genes were changed in the opposite direction from each other. More specifically, while women showed increased expression of genes affecting synapse function, men had decreased expression of the same genes. Women also had decreases in genes that impact immune function, whereas men had increased expression.

“These results have significant implications for development of potential novel treatments and suggest that these treatments should be developed separately for men and women,” says Dr. Seney.

The study was published in the journal Biological Psychiatry.