Genetic Factors Flashcards
What is MAOA (monoamine oxide A)
An enzyme that regulates metabolism of serotonin in the brain
What is the MAOA gene
The gene responsible for the activity of the enzyme MAOA in the brain- the low-activity variant of the gene is closely associated with aggressive behaviour
Outline a study which reveals the influence of the MAOA gene on aggression
Brunner et al. (1993) found that 28 males in a Dutch family, who had a history of impulsively aggressive behaviour (rape, attempted murder), had abnormally low levels of MAOA and the low-activity variant of the MAOA gene
Describe an additional study which supports the role of the MAOA gene on aggression
Mertins et al. (2011) found that high-activity variant of MAOA gene can lead to less aggression
What is the difference between MZ and DZ twins
MZ twins share 100% of their genes, whereas DZtwins share 50% of their genes
Which twin study revelas the influence of genes on aggression
Coccaro et al. (1997) found concordance rates of physical assault were 50% for MZ twins and 19% for DZ twin and found concordance rates of verbal aggression were 28% for MZ and 7% for DZ twins
Which adoption study reveals the influence of genes on aggression
Hutchings and Mednick et al. (1975) found that a significant number of adopted boys in Denmark with criminal convictions had biological parents with convictions for criminal violence
Describe a study which has suggested that aggression is a result of a gene-environment interaction rather than just genes in isolation
Caspi et al. (2002) determined that children with low-activity variant of MAOA gene were more likely to show anti-social behaviour, only if they had been maltreated as a child
Why is using different methods to measure aggression an issue
Makes it difficult to draw valid conclusions about the role of elf genetic factors if research findings vary depending upon how the aggression is measured
Describe a study which suggests the influence of multiple genes on aggression and not just the MAOA gene
Stuart et al. (2014) found males who inflicted IPV were more likely to have the low-activity variant of the MAOA gene and the serotonin transporter gene (5-HTT)
