Biological genetic explanation Flashcards
what is the basis of the genetic explanation
one/two genes predispose individuals to criminal behaviour
what is the biology of the MAO-A gene
it produces an enzyme to break down dopamine, serotonin and norepinphrine. if this enzyme isn’t produced the neurotransmitters aren’t broken down so constantly bind at the post-synaptic neurone so we are constantly motivated to fight
what does a mutation of the MAO-A gene cause
Brunner syndrome which results in mood swings, an IQ lower than average and violence
what is CDH13 responsible for and what is the full name
Cadherin 13 is responsible for increasing signals sent between cells
what is epigentics
changes to how a gene is expressed. criminal behaviour is caused by biological faults but has to be triggered by the environment e.g. childhood maltreatment
explain Caspi et al’s study
used data from a longitudinal study in New Zealand of 1000 people. they assessed anti-social behaviour in 26 year olds and found 21% of men with mutated MAO-A genes had experienced maltreatment as babies. they had been responsible for 44% of the total seen violent crimes
E-support from Brunner. explain his study and results
analysed the DNA of 28 members of a dutch family who had histories of impulse and violent criminal behaviours (e.g. rape) and found they all shared a gene that led to low levels of MAO-A
E-support for Tiihonen. explain his study and results
examined 900 Finnish offenders and found evidence of low MAO-A and CDH13 activity. they esteemed 5-10% of criminal behaviour in Finland is due to genetic abnormalities
E-counter argument. what is the stat that backs up the idea of epigenetics? and explain
30% of men have the warrior gene but not 30% of men are in prison. the men may have it but the environment has not triggered it
E-adoption studies. explain what Crowe found
adopted children with a biological parent holding a criminal record had a 50% greater risk of a criminal record by 18 years old compared to 5% control group without parents holding criminal records
E-twin studies. explain Christiansen study
studied 87 Mz and 147 Dz twins and found concordance rates of 33% for Mz and only 12% for Dz
E-twin studies. explain Large investigation
investigated 13 pairs of Mz and Dz twins. one of each had spent time in prison. 10 of the Mz twins had both been to prison, but only 2 of the Dz twins
E-may only account for violent crimes. what did Lynn Findley say
crime is a social construction not natural. so people have made it and it includes many different behaviours. it is hard to explain as genes interaction with environment. this may be an oversimplification
