Double helix

Genetic link between personality traits and psychiatric diseases is finally established. Scientist discovered that certain personality traits could influence risk factors for psychiatric disorders.

The five factors model chart
The five factors model ( FFM )

The five factors model also know as big five represents five basic dimensions of personality.  The five factors have been defined as:

  • Openness to experience – describes a person’s tendency to think in abstract, complex ways. People with this traits are likely to be creative, imaginative, adventures.
  • Conscientiousness – describes a person’s ability to exercise self-discipline and control in order to pursue their goals.
  • Extraversion – describes a person’s inclination to seek stimulation from the outside world, especially in the form of attention from other people. Extraverts engage actively with others in order to earn friendship, admiration, power, status, excitement, and romance.
  • Agreeableness –  describes a person’s tendency to put others’ needs ahead of their own, and to cooperate rather than compete with others. People who are high in Agreeableness experience a great deal of empathy and tend to get pleasure out of serving and taking care of others. They are usually trusting and forgiving.
  • Neuroticism – describes a person’s tendency to experience negative emotions, including fear, sadness, anxiety, guilt, and shame. While everyone experiences these emotions from time to time, people high in Neuroticism seem especially prone to them.

It has already known that the personality is partly linked to genetics thanks to the genome-wide association study. The conducted twin studies show that around 40–60% of the variance in the Big Five is heritable, with some overlap in heritability between personality traits themselves. With those results, the following research will allow scientist to have a closer look at which parts of our DNA code affect certain aspects of our character.

The lead researcher Chi-Hua Chen explained that the biggest challenge was to characterize genetic variants associated with personality. They analyzed genetic data including around 140, 000 genetic samples. We already know that there is the influence of genes and environment in creating our personality, but the question was how these two factors balance out.

Researchers found the link between genes and traits. For example, the genes WSCD2 and PCDH15 are connected to extraversion, while the gene L3MBTL2 and the chromosome 8p23.1 are tied to neuroticism. Further examination shows that genes related to neuroticism and openness to experience were clustered together in the same regions as genes linked to certain psychiatric disorders. Also, it is discovered a genetic correlation between extraversion and attention deficit hyperactivity disorder (ADHD ). Openness traits are connected with schizophrenia and bipolar disorder. Neuroticism was linked with depression and anxiety.

On the other side, there was no find connection between mental illnesses and agreeableness or conscientiousness. Still, these research are at the begging. For now, it is unknown which are the specific variants underlying the correlations.