An international team from the Vrije Universiteit in Amsterdam has identified 939 new genes involved in the development of emotional intelligence and stability. The new genes are added to the 77 identified in previous studies.
For the first part of the research, the researchers involved a sample of about 270,000 subjects. In the second, on the other hand, they involved about 500,000 people. The second part focused on the genetic basis behind some mental disorders. On this occasion, scientists have identified a personality trait that increases the risk of incurring these problems.
To identify the genes in question, the researchers relied on genome-wide association studies. These collect the genetic variations of hundreds of thousands of genes by analyzing the presence and activities in thousands of subjects.
Scientists have identified high levels of expression in neurons in the hippocampus and striatum. These could be the genetic causes of the so-called fluid intelligence. The term fluid intelligence when an individual uses logical reasoning to find new solutions, no matter what knowledge you already have. It is in contrast to the crystallized intelligence, or the ability to make the best use of the knowledge that one has.
The study also identified a correlation between intelligence and Alzheimer's risk. Some genetic variants associated with intelligence appear to protect the brain from Alzheimer's and attention disorders. The researchers also focused on the genes on which emotional stability is based.
It seems that emotional stability resides in 599 genes. Some variants within these predispose emotional instability or neuroticism. Subjects who show variants are more likely than average to experience negative emotions. They are also more prone to depression and sometimes to schizophrenia.