Russian biologists studied genetic aspects of aggressive behaviour.
      
      Scientists collected blood samples from sportsmen and ordinary people and extracted DNA. Special genetic markers allowed studying variations of several genes, responsible for human aggressive behaviour.
      
      First target was the gene, coding serotonin carrier – 5HTT. Its function is taking serotonin away from synaptic trough after nerve impulse moved from one neuron to another. Key segment of 5HTT can be “short” and “long”, thus having different activity.
      
      Research showed that people, who had two “long” genes, were more aggressive than “short” gene owners, who also were more anxious. Sportsmen had “long” 5HTTs oftener and were more psycho-emotionally stable.
      
      Another target was the gene, coding dopamine degrading enzyme. Point mutation in this gene eliminates aggressiveness. Thus, owners of mutations in both genes are less aggressive than those with normal ones.
      
      Source: Science News