One million patients under the microscope. Behind the scenes of a historical experiment
An international team of over 120 scientists from different countries conducted the largest study to date aimed at understanding how our DNA influences personality development. The results published in the prestigious scientific journal Nature shed new light on the complexity of the human psyche. Experts analyzed data from as many as 46 different research groups, covering from over 600,000 to up to 1.14 million participants.
Researchers focused on the so-called the big five personality traits: extroversion, agreeableness, conscientiousness, neuroticism and openness to new experiences. The goal was to determine how much genes and how much environment accounted for differences in these key traits.
There is no “agreeable gene.” How thousands of puzzle pieces create our character
Research results clearly show that there is no single, decisive gene responsible for a given personality trait.
There is no single gene that makes someone open-minded or conscientious. Instead, we see that thousands of genetic differences, each of which acts to a small extent, but together, together with the environment, shape personality - emphasizes Prof. Henry R. Kranzler of the Perelman School of Medicine at the University of Pennsylvania.
In total, at least 1,260 common genetic variants have been identified that contribute to personality differences. However, researchers estimate that over 16,000 DNA variants may be involved in shaping each of the five main personality traits.
Nature versus nurture. Who's really in control?
Analyzes showed that genetics accounted for 5 to 9 percent of the differences in personality between people studied. Importantly, the influence of genes was very consistent regardless of the participants' age, region of residence or the opinions of close people.
By comparing people from the same family, scientists have found that most associations between genetic variants and personality are not due to environmental factors common to the family. This is an important observation because factors such as upbringing or environment may distort previous results of research on the genetics of behavior.
Your personality and health. What reveals neuroticism and what does conscientiousness?
The findings also showed that genetic determinants of personality are associated with various aspects of health, including a tendency to mental disorders, addictions and physical condition. For example, genetic variants predisposing to neuroticism were associated with a greater risk of mental problems, while genes favoring conscientiousness were associated with a lower risk of substance abuse and a greater tendency to be physically active.
However, as researchers emphasize, these are statistical dependencies concerning large groups of people. Research results do not allow predicting the personality or behavior of specific people.
DNA is not a verdict. What awaits us in the future?
These results give us a new tool to investigate why personality is linked to so many aspects of health and behavior. At the same time, they confirm an important truth - our DNA influences our personality and future, but does not determine them - sums up Prof. Kranzler.
Experts point out that further, even larger research is necessary, including people of more diverse origins and from different cultural backgrounds. This will help determine whether similar genetic relationships exist in other populations around the world.
