Bioloical Explanations: Gentic Explanations Flashcards
How does the genetic crime explain crime?
Through genetics which propose that there are one or more genes which individuals inherit which predisposes them towards criminality
What is twin studies do?
Compare the difference between identical monozygotic twins and non identical dizygotic twins
What is the difference between MZ and DZ twins?
- MZ twins share 100% of the same genes and environment
- DZ twins share 50% of genes and 100% of the same environment
What is concordance rates?
If behaviour is caused by genes then we should expect MZ twins to be more similar than DZ twins
What did Raine do?
Reviewed a range of research studies on the delinquent behaviour of twins and found that for MZ twins the concordance rates were 52% whereas it was 21% for DZ twins
What genes have been linked to possible cause of criminality?
- Monoamine Oxidase A (MAOA)
- CDH13
What does MAOA do?
Controls the production of dopamine and serotonin which have been linked to increased aggression
What had CDH13 been linked with?
Substance abuse and attention deficit disorder
What did Tiihonen et al do?
Analysed the genetic makeup of 900 criminals and found that a combination of MAOA and CDH13 meant that offenders were 13 times more likely to have a violent offending past
What is the diathesis stress model?
A biopsychosocial model which says that although genes will likely play a role in the development of criminality they are likely to be mediated environmental factors
What are epigenetics?
Propose that genes are switched on or off by environmental factors
What did Caspi et al find?
12% of those men with low MAOA genes had also experienced maltreatment when they were babies. These 12% of the 1000 person sample accounted for 44% of all violent convictions
What are 3 evaluation points?
- Twin explanations: MZ twins are tested more similarly
- Other explanations: stress of adoption could account for behaviour
- Influced by family: social learning not genes?
