1 April 2020
In a scientific first, international collaboration has led to the development of a genetic map of the cerebral cortex. This could pave the way to a better understanding of psychiatric and neurological conditions.
The cerebral cortex is the relatively thin outer ‘gray matter’ of the brain which is crucial for thinking, information processing, memory and attention. The surface area and thickness of the cortex have been linked to a number of psychiatric traits including schizophrenia, bipolar disorder, depression, attention deficit hyperactivity disorder and autism.
To gain a better understanding of this part of the brain, over 360 scientists from 184 different institutions have contributed in a global effort to find more than 200 regions of the genome and more than 300 specific genetic variations that affect the structure of the cerebral cortex and likely play important roles in psychiatric and neurological conditions.
Looking at MRI scans and DNA from more than 50 000 people to identify 306 genetic variants that influence brain structure, researchers used the information to ‘shed light on how genetics contribute to differences in the cerebral cortex of individuals.’
Among the findings, published in the journal Science, it was concluded that people at genetic risk for depression or insomnia are genetically inclined toward having a lower cerebral cortex surface area, while people with genetic risk for Parkinson’s disease tend to have a high surface area. In addition, the researchers noted that the vast scale of the project allowed for the discovery of specific genes that drive brain development and aging in people worldwide.
One of the study leaders and co-senior author Jason Stein PhD, assistant professor in the Department of Genetics at the University of North Carolina School of Medicine, US, said ‘Most of our previous understanding of genes affecting the brain are from model systems like mice.’ Citing the pitfall of this model Stein added ‘The genetic basis for a mouse is very different than the genetic basis for humans, especially in the noncoding regions of the genome.’
The new research has been able to pinpoint genetic variants associated with cortex size and structure. Researchers say that the findings can be used ‘to help answer important questions about the genetic influences on the brain and how they relate to numerous conditions.’