Researchers at The University of Manchester are testing our genetic disposition to depression with a unique Internet test.
The team, based at the Neuroscience and Psychiatry Unit (NPU), in the Faculty of Medical and Human Sciences, has set up a website (www.newmood.co.uk) where would-be volunteers can see how prone they may be to depression by identifying the emotions on people's faces and taking a gambling test.
The team aims to recruit more than 1000 UK volunteers for further tests as part of the five-year, EU-funded project called NewMood - New Molecules in Mood Disorders. They have already discovered how anti-depressants such as Prozac can affect how the brain reacts to fearful faces and which parts of the brain react to fear.
Professor Bill Deakin explains: "Anxiety is a contagious emotion. When you see other people who are anxious, as a primate you feel anxious as well. Our brains are wired to see anxiety - it makes sure we are safe. This is a fascinating test and, during further testing, we will be able to see which parts of the brain light up, or work harder, when you see a fearful face. Depressed people are more likely to see sadness or fear in a neutral face.
"The gambling test, where volunteers choose from pairs of spinners to 'win' money, will show us which parts of the brain light up when you are working for a reward. Depressed people are less affected by reward and more likely to give up easily as the test goes on."
Volunteers for this research study will be asked to fill in a confidential questionnaire and provide a mouth swab for genetic analysis. The team will then compare the DNA with the questionnaire group data.
In the other EU NewMood centres, rats and mice are also being tested for their predisposition to depression using similar reward and anxiety measures. When offered sweet-tasting drinks, depressed animals show no preference, much as humans lose pleasure in eating and often lose weight when they are depressed. And when given the opportunity to explore a new location depressed animals are more wary and take longer to emerge from dark corners, much as depressed humans avoid social situations.
"All humans have the same genes and they are very similar to those in all mammals - we turn out differently from each other because we inherit different versions of the same genes which can vary in their activity" Professor Deakin says. "We can see what genetic traits towards depression these animals have, then compare them with the same genes in the human DNA.
"Depression is a common trait like height or body build and, just like those, we suspect there are lots of genes involved. By measuring the important possible factors that can lead to a tendency to depression across a large number of individual people, we hope to find which ones act together to cause depression. Ultimately, this will help us to develop new ways of preventing and treating this illness."
Depression is common illness affecting 10-20% of the population at some time in their life and is twice as common in women as in men. Treatment can be very effective, but may not help everyone. The causes of depression are a mixture of genetic tendency, personality factors, difficult circumstances and life experiences, and the big challenge is trying to understand how these work together to lead to depression.
Professor Deakin adds: "We have already made two discoveries through our work so far. We have found that anti-depressants such as Prozac affect how the brain reacts to fearful faces, and also which parts of the brain react directly to antidepressants."
The University of Manchester is leading 13 institutions in ten countries in the NewMood project. Four institutions are testing humans and each need 1000 volunteers. Those who take part in this study could win £100 in a prize draw.