Researchers found creative people such as musicians and dancers were up to 25% more likely to carry gene variants linked to bipolar and schizophrenia than non-creative individuals.
First study author Robert Power, of the Institute of Psychiatry, Psychology and Neuroscience (IoPPN) at King's College, London in the UK, and colleagues publish their findings in the journal Nature Neuroscience.
Creativity is defined by researchers as "novel approaches requiring cognitive processes that are different from prevailing modes of thought or expression."
Such approaches are normally adopted by people who have visionary professions or hobbies, such as artists, musicians, actors, dancers and writers. But does creativity increase an individual's risk of mental illness?
Past research has found that mental illnesses - particularly bipolar disorder - are more common among people with relatives who have creative professions. However, researchers have been unable to identify the mechanisms underlying this association. For their study, Power and colleagues wanted to find out.
"For most psychiatric disorders little is known about the underlying biological pathways that lead to illness," says Power. "An idea that has gained credibility is that these disorders reflect extremes of the normal spectrum of human behavior, rather than a distinct psychiatric illness."
"By knowing which healthy behaviors, such as creativity, share their biology with psychiatric illnesses," he adds, "we gain a better understanding of the thought processes that lead a person to become ill and how the brain might be going wrong."
Creative professionals '25% more likely to carry bipolar, schizophrenia gene variants'
With the help of researchers from deCODE Genetics - a biopharmaceutical company in Iceland - the team was able to analyze data for 86,292 people from Iceland's general population.
The researchers calculated genetic risk scores for schizophrenia and bipolar disorder for each individual, and they identified the creativity of each person - determined by their profession or enrollment in national artistic societies of dancers, actors, musicians, writers and visual artists.
The team found that individuals whose profession was a painter, musician, writer or dancer were 25% more likely to carry gene variants related to bipolar or schizophrenia than those in less creative jobs, such as manual laborers and farmers.
What is more, people who were a part of national artistic societies were 17% more likely to carry gene variants for bipolar or schizophrenia than individuals who were not members of these societies.
Explaining what the results mean, Power says:
"Our findings suggest that creative people may have a genetic predisposition toward thinking differently which, when combined with other harmful biological or environmental factors, could lead to mental illness."
Talking to The Guardian, study co-author Kari Stefansson, founder and CEO of deCODE, notes that the genetic factors identified in this study that increase the risk of mental illness only explain around 0.25% of the variation in a person's creativity.
This means other genetic factors may influence creative ability, or it could be influenced by a person's social environment or life experiences.
Still, Stefansson believes their finding identifying a genetic link between creativity and mental illness is an interesting one. "It means that a lot of the good things we get in life, through creativity, come at a price," he told The Guardian. "It tells me that when it comes to our biology, we have to understand that everything is in some way good and in some way bad."
In 2011, Medical News Today reported on a study suggesting creative thinkers may be less honest and more likely to cheat than non-creative thinkers, possibly because they are better at devising excuses to explain their actions.