genetics

• what is Monoamine oxidase A (MAOA)?

  a gene that codes for an enzyme that breaks down important neurotransmitters in the brain, including dopamine and serotonin.
• • what is research into maoa?
  •  brunner analysed data of violent criminals and found that they all shared a particular genes which caused abnormal low levels of madoa 
• • what is CADHERIN 13 gene?
  • a gene involved in neural connectivity 
• • research into cadherin 13?

  In a study of 900 offenders there was evidence found for low activity in this gene and evidence low maoa

  • 5-10% all violent crimes in finland is due to these abnormalities individuals with this high risk combination were 13 times more likely to have a history of violent behaviour.
• • Raine= mz- 52% concordance rate (delinquent behaviour), 21% dz 
  • genetic componenets, high concordance= share more genetic
  • not 100% (share 100% and 50% DNA) =not attributed to just genes - environmental factors
  • criticism= assumption they only differ in genetics
  • mz shared environment more similar than that of non identical twins because they are treated more similarly they can suffer from identity confusion
  • increase concordance= environmental factors like how they are treated
  • reductionist
• • Caspi -1000 male children low level is maoa associated anti social behaviour (only if maltreated) . Low not maltreated= no asb
  • anti social offending behaviour not just genetic + interaction between genes+ environment. T
  • diathesis stress biological or genetic vulnerability,eg. low maoa interacts eg maltreated or not causes this vulnerability to be expressed,
  • not attribute just genetic environment equally as important
  • beta biased - males offending behaviour