Friday, June 02, 2006

Gene Variant Biases Brain Towards Aggression

This report from the NIH News notes that a version of a gene previously linked to impulsive physical violence biases the brain towards impulsive, aggressive behaviour. People with this gene variant (especially males) have a hyperactive alarm system and an under-active impulse control circuitry. But like all complex phenotypes, having this version of the gene does not mean a person will necessarily display this behaviour. As the report states:

“These new findings illustrate the breathtaking power of ‘imaging genomics’ to study the brain’s workings in a way that helps us to understand the circuitry underlying diversity in human temperament,” said NIH Director Elias A. Zerhouni, M.D., who conducted MRI studies earlier in his career.

“By itself, this gene is likely to contribute only a small amount of risk in interaction with other genetic and psychosocial influences; it won’t make people violent,” explained Meyer-Lindenberg. “But by studying its effects in a large sample of normal people, we were able to see how this gene variant biases the brain toward impulsive, aggressive behavior.”