An international team of scientists has identified 1,260 genetic variants associated with personality traits, including extraversion, conscientiousness, and neuroticism. However, common DNA variants explain only 5–9% of the differences between individuals. The findings of the large-scale study were published in the journal Nature.
The scientists combined data from 46 research groups. Depending on the analysis, the study samples ranged from 611,000 to more than 1.1 million people. The researchers examined genetic associations with the five major personality traits: extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience.
The researchers identified 1,260 specific DNA variants that were statistically associated with personality traits. However, further analysis showed that the genetic influence is much broader: according to their calculations, thousands of independent genetic variants contribute to each of the five major personality traits, with an average of approximately 16,000 variants.
“This means that personality is shaped by numerous genetic differences, each of which has a very small effect. No single gene is responsible for an individual personality trait. The environment also plays an important role,” the scientists explained.
The researchers also found genetic links between personality traits, health, and behavior. For example, variants associated with neuroticism were linked to an increased risk of mental disorders. Genetic characteristics associated with conscientiousness correlated with lower substance use and more frequent physical activity.
The scientists emphasize, however, that the identified associations cannot be used to accurately predict an individual's behavior. Genetic variants explain only a small proportion of personality differences, and the findings do not mean that particular genes directly cause specific actions.
“Our DNA influences our personality and our future, but it does not determine them,” said study co-author Professor Henry Kranzler of the University of Pennsylvania.
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