Some people who take big risks on the stock market can blame their genes for their behaviour, work suggests.
The US scientists say their findings might give an insight into one reason for the current economic slump.
The Northwestern University team found two genes that regulate the hormones dopamine and serotonin could predict whether a person would gamble.
The same genes have already been linked to addiction and negative emotions, PLoS ONE journal says.
In the study, 65 volunteers were asked to make investment decisions – some high risk and some low risk – as part of an experiment.
The investigators collected saliva from each participant to look at the DNA.
They discovered that the volunteers who took the most risks had a particular version of a dopamine-regulating gene and another gene that regulates serotonin.
Specifically, people with the short serotonin transporter 5-HTTLPR were far more cautious than those with the long version.
Similarly, people with the 7-repeat allele of the dopamine DRD4 gene took more risks than those with other versions of the same gene.
Although the researchers say less than 30% of variation across people in risk-taking comes from genetics, the rest comes from experience and upbringing, they believe their findings do shed some light on the current financial crisis.