ADHD News & Research

15 Genomic Regions Linked to Certain Depression Diagnoses

A new study identifies 15 major genetic loci that are associated with a risk of depression in people with European ancestry — potentially opening up new pathways for diagnosis and treatment.

August 11, 2016

While depression is often characterized by stock images of people looking sadly out windows, in real life it defies categorization. Despite affecting nearly 16 million Americans annually, depression can look totally unique in each person who lives with it — even within family groups who fall victim to depression’s high level of heredity. Its wide range of symptoms and presentations has long led researchers to hypothesize that it originates across multiple genes, rather than just one or two. Now, a study has tentatively confirmed that hypothesis and pinpointed at least 15 of those genes — at least in depression patients who are of European ancestry.

The study, published August 1 in Nature Genetics, relied on data gathered by a genomics company called 23andMe. Researchers analyzed the genetic makeup of more than 300,000 individuals of European descent (all of whom consented to be a part of the research). Of those, approximately 75,000 had been previously diagnosed with or treated for depression. Their genes were analyzed for common variations, with the results combined with two other genetic studies compiled with additional data from the same company.

The merged results identified 15 genomic regions that were found to be associated with the depressive population — many of which were tied to genes that are known to be involved in brain development. A few of the genes were also connected to other psychiatric diagnoses, like anxiety disorders, while others were thought to be related to epilepsy or intellectual disabilities.

Identifying such clear genetic links for depression is the first step to updating current treatment methods in favor of more effective brain-based alternatives, the researchers say — as well as laying the groundwork for updating outdated public perceptions of the disorder.

“Finding genes associated with depression should help make clear that this is a brain disease, which we hope will decrease the stigma still associated with these kinds of illnesses,” said study co-author Dr. Roy Perlis, of the Department of Psychiatry and the Center for Human Genetic Research at Massachusetts General Hospital.

Plus, he adds, “Identifying genes that affect risk for a disease is a first step towards understanding the disease biology itself, which gives us targets to aim for in developing new treatments.”

The study also opens the door to further research using data collected by private genetic sequencing companies, Perlis says — a huge database of information that has mostly been ignored by researchers up until this point.

“The neurotransmitter-based models we are currently using to treat depression are more than 40 years old, and we really need new treatment targets,” he said. “We hope that finding these genes will point us toward novel treatment strategies.”