Depression: Nature v Nurture

"The debate whether it’s nature or nurture that dictates your life has raged since the time of Darwin. But the latest DNA testing and our understanding of genetic action, is sending us into a new era.

Jonica Newby steps into the future by taking a DNA test not yet available to the public. The test will reveal whether she has the double gene for depression. If she does, science says she will be prone to severe depression during stressful times.

The story captures the moment when the news is delivered and discusses the implications of knowing your genetic destiny.

The link between genes and behaviour is being closely studied in Dunedin, New Zealand. Similar attempts over the last 20 years have failed – but this team did something unusual. They cross-referenced the genes with the person’s background – with extraordinary results.

Their first discovery has been hailed as a gene for violence. We explain how it works – people who have one version of the MAOA gene are not readily able to damp down their stress response in the brain. But it’s only a problem if they have a stressful childhood – most people with the wrong gene/environment combination have ended up in jail for violent crime.

And now, the same team has found a gene for depression. It involves a different neurotransmitter – in this case using the serotonin system – but the same applies; combine a certain gene with stressful life events, and these people are far more likely to develop depression.

The debate between nature and nurture may soon be declared a tie.

Combine the two and it seems you may have a powerful predictor of human behaviour. The discovery will change society forever from our legal system, to healthcare and insurance and even perhaps what it means to be human".

Click the link under the headline Nature Nurture to launch a 10 min ABC documentary on nature v nurture in aggression and depression.