Depression has been my companion since at least the age of 10. My father suffered from it. Probably one of his parents did, but as a child of immigrants in an era where mental illness was anathema, that secret remains in the old country.
Some of my siblings have depression, as does one of my children.
Well-meaning religious people have told me my depression is a spiritual problem — pray more, pray differently, find Jesus.
Depression is a whole-body illness, affecting the mind, body and behavior.(2) Friends have been puzzled when I’ve explained depression’s command of the body, how it renders me inert and lifeless.
A Facebook acquaintance once diagnosed me as reading too many books.
A lack of knowledge about mental illness leads to discrediting or shaming individuals who have it, perpetuating stigma, as I wrote in “The Evolutionary Benefits of Mental Illness.”
Knowledge reduces the stigma of mental illness, and to that end a recent study from Massachusetts General Hospital indicates depression is genetic, at least if you’re European.(1)
While depression has long been understood to run in families, researchers have previously been unable to identify genetic variants that influence the risk.
Researchers used DNA samples and data from the commercial genetic-testing company 23andMe. Among the participants were 300,000 individuals of European ancestry who agreed to be included.
Seventy-five thousand of these self-reported having, or being treated for, depression.(1)
In addition to contributing DNA samples, study participants completed surveys and provided medical histories.
Researchers combined the 23andMe data with a smaller study involving 9,200 other individuals with depression, and used 9,500 addition people as a control group.
The study revealed 15 regions of the genome associated with depression in those with European ancestry, located near genes associated with brain development.
Finding genes associated with depression helps confirm that depression is a disease, not a character defect, and helps to relieve stigma.(1)
While this study focused on people of European descent — 4.8 percent of whom suffer from depression — approximately 8 percent of African Americans were found to have the illness, based on data from 2005.(4)
More than 90 percent of studies of the genetics of disease are conducted on people of European ancestry. In response to this imbalance, in 2011, 23andMe launched a project called “Roots into the Future,” a large-scale genetics study of African Americans.(3)
Forty-five thousand African Americans are currently participating, and the National Institutes of Health has recently given 23andMe a grant to create “a new analysis pipeline” in order to overcome racial disparities in genetic research.(3)
A study showing a genetic link to depression in people of color is likely on the horizon.
Co-author of the Massachusetts General study Roy Perlis, MD, told Science Daily, "Another key takeaway from our study is that the traditional way of doing genetic studies is not the only way that works.” (1)
Tapping the existing store of genetic data, i.e., crowdsourcing the genome, may be the future of diagnosing and treating psychiatric illness. (1)
Reviewed August 23, 2016
by Michele Blacksberg RN
Edited by Jody Smith