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Hope Floats

© John McManamy

"Our goal is to get to a diagnostic system based on biology and genes."

When it comes to medical science sitting up and paying attention to our needs, we have been placed on the equivalent of hold. We have yet to catch the eye of the waiter, the guy behind the counter has not said, "next," and the person in the front door seems oblivious to our open trick or treat bag, to serve up just a few metaphors.

As Dennis Charney MD, who has recently joined the NIMH to head up their new mood and anxiety disorders research program, explained at the national NAMI Conference held in mid-July in Washington DC, the DSM-IV is based on symptoms rather than biology. The depression you suffer from may have a different physiology entirely than the depression of the person next to you, but the treatments available to us do not recognize this fact of life.

Then Dr Charney said: "Our goal is to get to a diagnostic system based on biology and genes ...We have a plan of how we can get there, a five or 10 year plan."

Do we detect a major sea change? Here's a brief glimpse into the future, according to Dr Charney:

Depression is not just a deficiency of serotonin. In some patients it may be parts of the serotonin system that break down. Prozac and its chemical cousins operate on the serotonin transport site, but there are also 15 or so different serotonin receptors. The serotonin 1A receptor, when not working right, for instance, appears to result in low serotonin in one half of depressed patients in the hippocampus and amygdala (the seat of emotion) of the brain, according to PET imaging done at the NIMH. This work needs to be replicated, Dr Chaney cautions, "but it shows what we can do," and suggests the possibility of developing a "serotonin agonist" to treat the problem.

Here's where it really gets interesting: If SSRIs work by blocking the serotonin transport site, there may be something wrong with the site to begin with. SPEC imaging indicates that one half of depressed patients may be affected this way. According to Dr Chaney, we are learning a lot more about the genetics of this site, and the next step would be to see if the genetic coding of this site corresponds with the imaging. Three studies are in progress.

Speaking of genes: The day of genetic blood screening appears right around the corner. For instance, if a particular gene says you will respond to Paxil, your doctor will say let's try Paxil.

Back to biology, there is the HPA axis, which produces CRH which secretes