Biological Explanations - Genetic Explanation

Question 1

W hat is the genetic explanation?

Answer 1

_ They suggest offenders inherit a gene or combination of genes that predispose them to commit crime
- The importance of genes is illustrated in twin and adoption studies.

Question 2

What happens in the twin study - Lange (1930)

Answer 2

_ Investigated 13 identical MZ and 17 non identical DZ twins where one of each twin has served time in prison.
- 10 of the MZ twins and 2 of the DZ twins where one us each twin had served time in prison.
- 10 of the MZ twins and 2 of the DZ twins nah a co- twin who had been in prison.

Question 3

What does Christiansen (1977) twin study show?

Answer 3

• Studied over 3,500 pairs of twins of which one twin-of which one twin was a known offender.
• The concordance rate for MZ twins committing crime was 35% and DZ twins was 13%

Question 5

What was Raine (1993) study on twins?

Answer 5

Reviewed criminal twin studies and found 52% concordance for M2 twins compared to 21% for Dz twins

Question 6

What are candidate genes?

Answer 6

• Refer to genes that are suspected to be involved in a particular trait or disorder based on their known function or known genome.

Question 7

How do candidate genes link to criminals?

Answer 7

_ Tiinohen et al 2014 - carried out genetic analysis of 900 offenders in Finland and found abnormalities on 2 genes which are associated with violent crime - the MACA gene and CDH13 gene.
- these were significantly lower amongst genders.
- individual with this combination were 13 times more likely to have a history of violent behaviour.
- he estimated these gene abnormalities l to account for 5-100 % of all violent crime in Finland

Question 8

Identify which neurotransmitters in the brain the MAOA gene and explain now this may cause violent benaviour

Answer 8

• It regulates serotonin in the brain and has been linked to aggressive behaviour

Question 9

Which disorders have been linked to CD H 13 gene been linked to?

Answer 9

_it has been linked to substance abuse and attention deficit hyperactivity disorder

Question 10

Explain through diathesis stress model.

Answer 10

_ A tendency toward al allending behaviour may come through the combination of a genetic predisposition and biological and psychological trigger - eg being raised in a dysfunctional environment or having criminal role models