twin research

• Since twins share 100% of the same genes they should behave in the same way. According to the criminal gene, if one twin is a criminal then the other will be.
• No research has ever supported a complete genetic link for criminality. But research is carried out to investigate genes linking to criminal behaviour by studying MZ twins.
• Concordance rates are used, the higher the rate the more likely a behaviour is genetic. If the concordance rate is higher for MZ twins over DZ it could show behaviour is genetic.