6.1.1 - XYY Personality

Question 1

What is XYY?

Answer 1

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

Question 2

Characteristics

Answer 2

• Flat feet
• Belly fat
• Acne
• Tall
• Behavioural
  difficulties
• Lower iq (normal range)

Question 3

Thielgaard

Answer 3

Supporting.
Studied blood samples of over 30,000 men, XYY have lower levels of intelligence and more aggression compared to normal men.

Question 4

Gotz et al

Answer 4

Supporting.
34,000 infants scanned, compared XYY with controls, higher rate of crime and anti social behaviour.

Question 5

Holin

Answer 5

Opposing.
No significant correlation between XYY and aggression.

Question 6

Correlational

Answer 6

Weakness.
No cause and effect.

Question 7

Other factors

Answer 7

Deterministic - scapegoat.
Can’t explain female criminality.

Question 8

AO1

Answer 8

• 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

Question 9

Strength

Answer 9

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)

Question 10

AO1

Answer 10

• 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

Question 11

AO1

Answer 11

• May lead to behavioural symptoms
• Impulsivity, explosive temper, ADHD

Question 12

AO1

Answer 12

• Phenotypic characteristics such as tall, acne and flat feet
• May feel different and insecure