Gene therapy proposed to treat depression

A NOVEL treatment for depression may soon get the go ahead: injecting genes directly into the brain. It would be the first attempt to treat a psychiatric illness with gene therapy.

A gene called p11 is vital for enabling neurons to respond to the neurotransmitter serotonin. A lack of p11 has been shown to lead to depression in humans.

To test whether gene therapy could help, Michael Kaplitt of the Weill Cornell Medical College in New York City and colleagues first demonstrated that mice lacking p11 showed symptoms of depression, failing to respond with the same vitality as healthy mice when exposed to challenges, such as showing decreased effort when having to swim to an island.

Next they injected viruses containing p11 directly into the nucleus accumbens of the mice lacking p11. This part of the brain is where a lack of p11 manifests itself as depression in humans. The team found this reversed the depression in the mice (Science Translational Medicine, DOI: 10.1126/scitranslmed.3001079).

Although the proposal to do the same in humans sounds drastic, Kaplitt points out that a similar procedure has already been used to deliver genes to the brain's of people with Parkinson's disease.

"We're already doing a primate study to support a potential human trial, so this is moving ahead very rapidly," says Kaplitt.