genetic explanations

• Genetic explanation

  Some psychologists believe that genes can be responsible for aggressive behaviours and can be inherited, passed from one generation to another.

  Twin and adoption studies have been used to show the impact of genetics on aggression.
• The MAOA gene


  Known as the 'warrior gene'

  gene that is responsible for the production of an enzyme also called MAOA, responsible for the regulation of neurotransmitters such as serotonin in the brain.

  Low activity of the MAOA gene results in irregular low levels of serotonin and is thought to be closely associated with aggressive behaviour.

  high dopamine and noradrenaline

  low serotonin
• Supermale

  A male individual displaying the XYY chromosome structure.

  Above average height and below average intelligence

  Evidence that they are predisposed towards violent crime
• Caccaro AO3 - Strength

  Caccaro studied aggressive behaviours in MZ twins (share 100% of genetic information) and DZ (share 50%) adult male twins. They found that concordance rates were 50% in MZ twins and 7% in DZ twins.
• Stuart et al AO3 - strength


  Stuart et al (2014) studied 97 men who had been involved with inflicting domestic violence and were part of a batterer treatment programme. Findings: men with low activity MAOA gene were found to be the most violent perpetrators of DV.
• Limitations of genetic explanation

  A criticism of research into the role of genetic factors in aggression comes from opposing evidence suggesting that it's a combination of many genes and not specific candidate genes which causes aggression.

  
  

  Frazzetto (2007) did find an association between MAOA and aggression, but only if the individual had experienced significant trauma such as sexual or physical abuse when younger. This suggests that nature nurture interplay provides a more comprehensive understanding of the links between genetics, the environment and aggression rather than the MAOA theory alone.