The current treatment for depression is most often a Selective Serotonin Reuptake Inhibitors (SSRIs), which helps make serotonin available to help manage mood and stress. The question is why SSRIs work better for some than others.

A study done 10 years ago suggested that women respond better to SSRI treatment than men. Another study found that pre-menopausal women may also fair better than men receiving SSRI treatment. Exactly why women respond better to SSRI was the subject for University of Iowa researchers.

The study focused on the function of gene SLC6A4, which is associated with the availability of serotonin. For some reason women were found to have a variation in this gene than men based on analysis of 192 individuals. Although the researchers do not feel they have found a ‘depression gene,’ they have linked it to part of the depression process.

It is the variation in SLC6A4 that researchers suspect is a possible reason as to why women tend to respond better to SSRI therapy than men. The researchers found that methylation of the gene SLC6A4 occurs more often in women than men. It is specifically this variation in the gene that causes a person to have less mRNA, which is the genetic material that helps a gene make a protein. The mRNA’s role is important because the way you get a gene to a protein is through the RNA or mRNA messengers. Since there is less mRNA. it causes less serotonin to be available.

Researchers were unable to find a direct link between SLC6A4’s variation and depression. What they suspect is that the variant gene makes some people more prone to develop depression. Just because you might have the gene variant will not mean that you will develop a depression. It is like 2 people who are at genetic risk for osteoporosis. One of them runs on a regular basis, while the other swims. Of the 2 the runner is more likely to develop osteoporosis. In the case of SLC6A4’s variant gene the person who suffers more stress or abuse is more likely to develop depression.

With further studies the researchers hope that down the road it might be possible to identify those individuals who are more prone to depression and therefore to be able to target specific interventions of treatment.