It’s a common observation: Those who are the most creative are often fighting their own mental demons. Even as far back as Ancient Greece, it was noted that creative genius is often associated with mental illness. Now, a new study published in Nature Neuroscience claims that creative talent and psychiatric disorders may share genetic roots.

The research, carried out at King’s College London, suggests genes that increase an individual's risk of developing schizophrenia and bipolar disorder can also be used to predict how creative they are. Critics, however, have been quick to call the study out. While there could be a link, they say, it’s so tiny it's hardly worth worrying about, and that means its predictive ability is very limited.

The scientists of the study examined the genetic data for 86,000 Icelanders. They found that when certain genetic variations were looked at together, the combination could be used to predict psychosis. These combinations were found to double the average risk for schizophrenia and increase the risk for bipolar disorder by a third. The researchers then looked at how common these gene variants were within “creative individuals.” These people were defined as those who belonged to national art societies, such as dance, writing and acting.

After examining the occurrence of these genetic variants in the individuals sampled, the researchers report that they found a 17% increase in people who were members of artistic societies compared to non-members. The team then expanded the study to look at over 35,000 people from the Netherlands and Sweden, and discovered that those deemed to be “creative”—this time assessed through a questionnaire—were 25% more likely to carry the variations.

“By knowing which healthy behaviours, such as creativity, share their biology with psychiatric illnesses we gain a better understanding of the thought processes that lead a person to become ill and how the brain might be going wrong,” said Robert Power, one of the paper's authors. “Our findings suggest that creative people may have a genetic predisposition towards thinking differently.”

But the data is weak. The genetic variants analyzed only explained about 6% of schizophrenia cases and just 1% of bipolar disorders. The same variants also only explained about 0.25% of the variation seen in people’s creative ability. As David Cutler, a geneticist from Emory University who was not involved in the study put it: If artistic ability is a mile-long road where someone with high creativity stands at one end and someone with low creativity stands at the other, these genetic variations will only collectively explain about four meters (13 feet) of the distance. So not much at all, but not nothing either.

Others point out that the scientific definition of creativity, that of whether or not you belong to an art society or not, is also terribly poor. Going to a society or doing a “creative” occupation does not necessarily mean that you are creative, or that those who don’t go to one are necessarily uncreative. It also ignores the fact that many mental hospitals use art as a therapy for patients, so the fact that those with mental disorders might then be drawn to “creative” jobs could also skew the data.