Evaluation

• + Jacob er al found that there were overrepresented in the prison population being 15/1000 people in prison with XYY gene versus 1/1000 in the general population.
• + Adler et al (2007) argued that it is possible that aggressive and violent behaviour is at least partly deter mined by genetic factors.
• • Not all with XYY commit crime or act aggressively - it can affect them mentally as they are being labelled and they are not able to change at all.
• • The theory ignores environmental factors i.e uprising making it a reductionist theory.
• • A link doesnot mean XYY is causing criminality (correlation vs causation). Having an XYY can make you appear different which could lead to bullying. This could lead to criminality.
• • This theory cannot explain all men who show aggression or commit crime - It is too simplified and assuming.
• • Richard Speck, a commonly used case study to support XYY , did not have XYY syndrome.