6.1.1 - XYY Personality Flashcards
What is XYY?
Random mutation causes extra Y chromosome on sex pair.
No cure, can be helped by intervention.
1/1000 population, 15/1000 in prison population. - Jacobs et al
Characteristics
- Flat feet
- Belly fat
- Acne
- Tall
- Behavioural
difficulties - Lower iq (normal range)
Thielgaard
Supporting.
Studied blood samples of over 30,000 men, XYY have lower levels of intelligence and more aggression compared to normal men.
Gotz et al
Supporting.
34,000 infants scanned, compared XYY with controls, higher rate of crime and anti social behaviour.
Holin
Opposing.
No significant correlation between XYY and aggression.
Correlational
Weakness.
No cause and effect.
Other factors
Deterministic - scapegoat.
Can’t explain female criminality.
AO1
- A mutation on the 23rd pair producing XYY instead of the common XY
- It is seen in 1/1000 male births however 15/1000 in the prison population (Jacob’s)
- Tendency of crime
Strength
Gotz et al
- Screened 34,000 infants to compare XYY with controls
- Significantly higher frequency of anti social behaviour and rate of criminal convictions (against property usually not people)
AO1
- Hard to determine who has XYY
- Around 75% of men with XYY go undetected
- Can’t be cured however it is vital to diagnose early to reduce symptoms by therapy such as speech or educational therapy
AO1
- May lead to behavioural symptoms
- Impulsivity, explosive temper, ADHD
AO1
- Phenotypic characteristics such as tall, acne and flat feet
- May feel different and insecure