Genetic AO1

• What are candidate genes?

  A specific gene whose chromosomal location is associated with a particular condition
• What is the candidate gene associated with aggression?

  MAOA-L
• What role does the MAOA play?

  An enzyme, 'mopping up' neurotransmitters in the brain after a nerve impuslve has been transmitted from one neurone to another
• What is catabolism?


  The breaking down of a neurotransmitter - especially serotonin - into constituent chemicals to be recycled or excreted
• What does the MAOA-L gene do?

  Low MAOA acitivty, associated with aggressive behaviour
• What is the MAOA-L gene otherwise known as?

  Warrior gene
• What does the MAOA-L gene cause disruption to?

  metabolism of serotonin
• What does it mean if the metabolism of serotonin is disrupted?

  Fight or flight is constant due to lowered inhibition and lack of control over impulsive aggressive behaviour
• What are the three methods used to study genetic explanations of aggression?

  Genetic linkage, twin and adoption studies
• What are genetic linkage studies used for?

  To determine what genes are implicated in aggression, and whether are multiple genes (polygenic) or just one gene (candidate genes)
• What have twin studies suggested?

  Heritability and genetic factors account for about 50% of the variance in aggressive behaviour
• Why would we expect to find greater similarities in MZ twins than DZ twins?

  They share 100% of their genes
• How might the environment affect concordance rates between MZ and DZ twins?

  Raised together in the same environment
• What are adoption studies used for?

  To investigate the relative impact of genetics and the environment on aggression
• What do similarities in aggressive behaviour between an adopted child and their biological parents suggest?

  That genetic influences are prevalent
• What do similarities in aggressive behaviour between an adopted child with their adopted parents suggest?

  That environmental influences are prevalent