Biological Approach To Offending (genetic)

Question 1

What do we mean by the genetic explanation?

Answer 1

-genes consist of DNA. DNA produces ‘instructions’ for general physical features of an organism e.g eye colour and also specific physical features e.g neurotransmitter levels and size of brain structures. These impact on psychological features such as intelligence and mental disorders. Genes are transmitted from parents from parents to offspring.

-genetic explanations from crime suggest that would-be offenders inherit a gene, or combination of genes, that predispose them to commit crime.

Question 2

Twin studies

Answer 2

-Lange (1930) investigated 13 MZ and 17 DZ twins where one of the twins in each pair had served time in prison. Lange found that 10 of the MZ twins but only 2 of the DZ twins had a co-twin who was also in prison. Lange concluded that genetic factors must play a predominant part in offending behaviour.

-Christiansen (1977) studied 87 MZ and 147 DZ twin pairs where one of the twins in each pair has served time in prison. Christiansen found a concordance of 33% for MZs and 12% for DZs (concordance rate = both twins had served time in prison). Christiansen’s research supports the view that offending may have a genetic component.

Question 3

Twin studies AO1 paragraph

Answer 3

Genetic explanations for crime suggest that would be offenders inherit a gene, or combo of genes, that predispose them to commit crime.
Explain difference between MZ and DZ if concordance rates higher in one, what does it mean?

Question 4

Adoption Studies

Answer 4

-Crowe (1972) - 50% of adopted children whose mum had been in prison had also been arrested. Dotted children whose mother hadn’t been in prison, only 5% were arrested.
-Hutchins and Mednick (1975) - found that in a sample of male adoptees, 86% of those with a criminal conviction had a biological dad with a criminal record. 31% of the sample had committed a crime and their biological dad hadn’t.

Question 5

Adoption studies AO1 paragraph

Answer 5

Same summary statement as before.
Explain difference between children who have been adopted and go on to commit crime and those who don’t.

Question 6

Candidate genes

Answer 6

-Tiihonen (2014) conducted a genetic analysis of 900 Finish offenders. Each criminal was categorised violent or non-violent. They found abnormalities on two genes that may be associated with violent crimes.

-The MAOA codes for the enzyme monoamine oxidase A, which is important for controlling the amount of dopamine and serotonin in the brain and has been linked to agressive behaviour.

-CDH13 has previously been associated with substance abuse and ADD

-Those with the two genes were 13 times more likely to have a history of repeated violent behaviour.

Question 7

Diathesis-Stress Model

Answer 7

-its likely that even if genetics do have some influence on offending, it is at least partly moderated by the effects of the environment.
-a tendency towards criminal behaviour may come about through the combo of genetic predisposition and biological or psychological trigger. For example being raised in a dysfunctional environment or having criminal role models.