SAN DIEGO (CNS) - An international group of researchers, including some from UC San Diego, have identified a group of genetic variants that affect a person's penchant for taking risks, in a study published in Monday's issue of the journal Nature Genetics.
None of the 124 variants significantly affect a person's risk tolerance on their own and non-genetic factors still have more influence on an individual's risk tolerance, according to the researchers. The findings could, however, lead to further research into the biological mechanisms that influence a person's risk willingness.
``Being willing to take risks is essential to success in the modern world,'' said study co-author and UCSD professor Abraham Palmer. ``But we also know that taking too many risks, or not giving enough weight to the consequences of risky decisions, confers vulnerability to smoking, alcoholism and other forms of drug addiction.''
The research team measured risk tolerance via self reports from the study's subjects. Genetic variants tied to risk tolerance in general were also associated with risky behaviors like speeding and tobacco consumption.
The research team measured risk tolerance via self reports from the aligned with genetic influences for personality and neuropsychiatric traits such as bipolar disorder and schizophrenia.
``The most important variant explains only 0.02 percent of the variation in overall risk tolerance across individuals,'' said Jonathan Beauchamp, the study's senior author and an assistant professor of economics at the University of Toronto. ``However, the variants' effects can be combined to account for greater variation in risk tolerance.''
Researchers found that risk tolerance was not associated with dopamine or serotonin, the neurochemicals responsible for processing rewards and regulating a person's mood. However, the neurochemicals glutamate and gamma-aminobutyric acid were found to contribute to risk tolerance across the study's subjects. According to UCSD, glutamate increases neural communication while GABA prevents it.
A group of 96 researchers from the Social Science Genetic Association Consortium led the study.
``Our results point to the role of specific brain regions -- notably the prefrontal cortex, basal ganglia and midbrain -- that have previously been identified in neuroscientific studies on decision-making,'' Beauchamp said.
``They conform with the expectation that variation in risk tolerance is influenced by thousands, if not millions, of genetic variants.''