XYY Flashcards
(23 cards)
what does XYY theory focus on?
XYY theory focuses on the genetic makeup of a person
specifically abnormalities in chromosomal makeup during development of the 23rd pair of chromosomes (consists of determining sex)
what does XYY mean structurally?
XYY mean there is an additional chromosome at birth with an additional Y in males
what did Witkin et al find that XYY males consistently tend to have?
learning difficulties and poor attainment
what has further been suggested about XYY males?
may develop behavioural problems (having impulsivity or explosive temper)
May lack empathy, feeling no guilt or remorse
how can having impulsivity or explosive temper link to criminality?
Impulsivity and explosiveness results in overall increased aggressiveness leading to higher rates of violent crime
how do learning difficulties link to criminality?
Learning difficulties make it hard to learn from past experiences and consequences leading to higher rates of recidivism
what did Stockholm find in his study of 161 males with XYY?
there was a significant increase in the number of crimes compared to XY controls
This increase was seen in all crimes apart from drug and traffic related crimes
what did Stockholm find, after controlling certain factors?
when stocholm controlled for such factors as education, fatherhood and relationships he found the differences were very small
what did Stockholm conclude?
He concluded that raised risk of offending in XYY may be due to socio-economic conditions related to XYY but the additional Y was not a direct cause of criminal behaviour
what did Jacobs et al publish, supporting this theory?
Jacobs et al published their work linking the XYY chromosomal makeup and criminal personality
what did Jacobs et al find in his study?
He found 7 cases of the XYY makeup in a study of 196 individuals in the mental hospital of Edinburgh
Suggesting a potential link between them
what did re and Birkhoff complete that concluded no link after all?
However, re and Birkhoff completed a meta-analysis considering 50 years of evidence and concluded no link
what did Theilgaard look for and study?
Theilgaard looked for criminal gene (XYY) and studied blood samples of over 30,000 men
what did Theilgaard find, supporting the link?
Found XYY chromosome pattern of slightly lower intelligence levels than average and tend to be more aggressive towards people
Supporting a link between chromosomal abnormalities and heightened aggression levels
what is a positive about genetic testing?
Genetic testing is highly scientific and standardized, increasing objectivity and adding credibility to the results
what may be a problem with Theilgaards findings?
this link is only correlational
meaning XYY chromosome abnormality may not have caused heightened aggression and there may be a potential third factor such as social factors
what are some features of XYY syndrome
include learning difficulties, being above average height (7cm), widely spaced eyes and prone to facial acne
what can these features of XYY make it harder to do?
This may make it harder to integrate into society leading to increased frustration and withdrawals from society, resulting in lack of knowledge on social norms
what is another weakness of this approach?
Reductionist approach due to the overemphasis on the extra Y
how might this be better explained by labelling theory?
if someone has the appearance associated with XYY and labelled as having the ‘criminal gene’, that may define them and affect how society behaves towards them
what other explanation can also better explain this explanation?
May also be explained by social learning theory, learning through imitation (Bandura, growing up watching aggression and violence on TV
what application from this explanation can benefit society?
Can help us to identify issues early on and provide support from an early age
what else can we identify in society which with benefit those with XYY?
identifying issues with labelling in society, supporting and excepting those with XYY to make them feel supported, integrating them back into society
