An international team of scientists has identified more than 1,200 genetic variations linked to the Big Five personality traits. The study also found that genetic patterns associated with personality overlap with a broad range of life outcomes, including physical and mental health, longevity, education, career development, income, and daily habits.
The research was conducted by the Revived Genomics of Personality Consortium, an international collaboration that combined data from 46 study cohorts worldwide. Participants provided DNA samples and completed questionnaires measuring the Big Five personality traits: openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism.
These five traits describe relatively stable patterns in the way people think, feel, and behave. Researchers compared participants’ genetic data with their personality scores to identify genetic variations associated with each trait.
No single gene determines personality
“There is no single ‘personality gene,’” says Ted Schwaba, the study’s lead author and a professor in Michigan State University’s psychology department. “Personality traits are associated with many genetic variations, but even the largest effects of individual genetic variations are still very small. However, when many variations are considered together, their combined effects can be more meaningful.”
Although each genetic variation had only a small individual effect, the researchers found that groups of variations produced stronger and more consistent associations. These genetic patterns also appeared to apply across different populations and stages of life.
For example, genetic variants linked to extraversion in young adults in the Netherlands may also help predict extraversion among retired adults in the United States. Using a method that compared relatives with one another, the researchers found evidence that these associations could not be explained solely by people growing up in similar environments.
Even so, genetics represent only one part of personality development. The findings also confirmed that a person’s environment and life experiences play an important role in shaping personality.
How personality genetics may influence everyday life
The study found that genetic variations associated with personality overlap with genetic patterns linked to many other areas of life. These include mental and physical health, longevity, educational attainment, career choices and achievements, income, and how people are perceived by those close to them.
Some of these connections involve everyday behaviors and routines. Genetic variants associated with conscientiousness were linked to greater daytime activity. In contrast, variants associated with openness to experience and extraversion were linked to a greater likelihood of being a night owl.
The results also highlight the interaction between genetics and the environment. Rather than working independently, inherited traits and life circumstances can influence one another over time.
For instance, common genetic variants associated with openness to experience were linked to a greater likelihood of immigrating to a more cosmopolitan region. Living in a diverse and stimulating environment may then reinforce or further shape related personality traits.
Genetics, environment, and life outcomes
“Personality seems to be relevant everywhere you look, and I hope this study will encourage many other scientists to incorporate personality traits into their research fields,” Schwaba said. “For example, genetic variants associated with neuroticism predict more time spent in the hospital, which is relevant to doctors and health researchers. Genetic variants associated with openness to experience are linked to income and career changes, areas of interest to career researchers.”
The findings suggest that studying the genetics of personality could have implications far beyond psychology. This research may help inform future studies in medicine, public health, education, career development, and the workplace.
The research was supported in part by grants from the National Institute of Mental Health and the National Institute on Aging.
Source: www.sciencedaily.com