Outline & evaluate genetic factors in aggressive behaviour

Outline & evaluate genetic factors in aggressive behaviour

1. AO1

   • Coccaro '97
     • Aggression levels in adult twins, found 50% of direct aggression could be due to genes
   • Hutchings & Mednick '75
     • 14,000 Danish adoptions of boys that got criminal convictions. Significant number of the boys' biological fathers also had convictions
   • Montreal Uni
     • 667 Mono and Dizygotic twin pairs. Mums were asked to rate aggression at intervals through their early childhood. Supported genetic maturation hypothesis as environment has a short term effect while genetics have a long term effect. Supports the idea that people learn alternatives to aggression as they age
   • Brunner '93
     • Dutch family case study. Most of the men were violent, they were found to have faulty version of MAOA gene, which regulates the metabolism of serotonin. Faulty MAOA gene was linked to higher impulsivity