XYY syndrome Flashcards
What is XYY syndrome?
A rare genetic condition in 1 in 1000 males where they gain an additional Y chromosome on the 23rd pair, which changes their XY pairing to an XYY group, due to a genetic mutation at conception
What are the 7 symptoms of XYY syndrome (DTPILES)?
Delayed motor and language development - 50% have delayed speech development
Taller than average
Physically overactive
Impulsivity
Lower intelligence compared to their siblings - 15 points below
Easily distracted
Severe acne
How did XYY syndrome come to be associated with the concept of ‘super males’? (3 points)
Public misconceptions around XYY syndrome were that due to the extra Y chromosome, XYY men were ‘super males’ with lots of testosterone
This was due to their accentuating male physical symptoms (tall) and the psychological symptoms (physically active, easily distracted, alongside increased testosterone
The male hormone testosterone has regularly been linked to aggression and crime - Dabbs et al (1995) found a positive correlation between testosterone levels in saliva and involvement in violent crimes
What is the supporting and refuting evidence for the link between XYY syndrome and crime?
Supporting:
Jacobs (1965) and Leggett et al (2010)
Refuting:
Re & Birkhoff (2015) and Stockholm et al (2012)
Pygmalion effect
Mednick et al
How do Jacobs (1965) and Leggett et al (2010) support the link between XYY syndrome and crime? (3 points)
Jacobs (1965)
+ Reported that XYY men were over-represented in prisons
+ 15 in 1,000 XYY men in prisoners compared to 1 in 1000 in the general population
Leggett et al (2010):
Found with meta-analysis that males with XYY syndrome had IQs within average ranges but problems with their speech and language
How do Re & Birkhoff (2015) and Stockholm et al (2012) refute the link between XYY syndrome and crime? (2 points)
Re & Birkhoff (2015):
Found no evidence that XYY men have a predisposition to aggression, deviance, or offending behaviour
Stockholm et al (2012):
+ Raised risk of conviction for XYY men was due to socioeconomic conditions related to the syndrome’s symptoms
+ E.g. lowered intelligence and delayed language development
How does the Pygmalion effect refute the link between XYY syndrome and crime? (4 points)
The Pygmalion effect is ignited with the ‘super male’ label, leading to aggressive behaviour
An expectation of being disruptive and active causes the public to act negatively towards XYY men, making them believe that they are deviant
They internalise this belief and eventually fulfil it with deviant behaviours
Therefore, XYY men having more criminal convictions could be due to the incorrect “super-male” label and the subsequent self-fulfilling prophecy that occurs, rather than the extra Y chromosome itself
How does Mednick et al refute the link between XYY syndrome and crime? (3 points)
Mednick et al’s adoption study’s findings point toward an inherited genetic condition as an alternate criminal explanation
They found that if a person’s biological parents had been convicted of a crime, then they were nearly twice as likely to be convicted of a crime themselves
Perhaps biologically determined personality traits such as an inherited PEN criminal personality could determine criminality as Eysenck proposed
