Researchers discover DNA region linked to depression

Researchers at Washington University School of Medicine in St. Louis and King's College in London have independently zeroed in on a chromosome 3 DNA region related to depression.

The findings come via two studies---both published in the American Journal of Psychiatry. Family studies have indicated that depression risk is influenced by genetics. The two studies have identified a DNA region with up to 90 genes.

These findings aren't going to benefit patients right away, but they can help researchers understand depression at a genetic and molecular level. More research will be needed to specifically narrow down parts of the genome that influence depression.

What's notable about these studies is that they collected two data sets for different purposes and studied them in different ways. Both studies were led to chromosome 3. In other words, depressed siblings in both studies had the same gene variations in that DNA region.

Here's a look at the two studies:

• The Kings College London followed more than 800 families in the U.K. with recurrent depression. The focus of the study revolved around depression episodes.
• Washington University examined 91 families in Australia and 25 more in Finland. Washington University picked its participants because they were heavy smokers. Smokers are more likely to have major depression.

Neither team isolated the genes contributing to depression risk, but the area is a part of the chromosome known to house the metabotropic glutamate receptor 7 gene (GRM7). GRM7 and major depression have been associated in other research.

Michele L. Pergadia, PhD, research assistant professor of psychiatry at Washington University, said that the next step will be to exchange notes with the researchers at Kings College to learn more. The two research camps may also combine data sets to see if chromosome 3 maintains a significant effect.

This post was originally published on Smartplanet.com