Bio explanation of crime:XYY syndrome

Question 1

What is XYY?

Answer 1

when a male has an extra Y chromosome in his 23rd pair of chromosomes-47 instead of 46

Question 2

Prevalence

Answer 2

1 in 1000 male births-not inherited but random occurrence at conception
Jacobs et al-overepresentation of XYY in prisons-15 in 1000
Difficult to determine who has the syndrome-around 75% cases are not detected

Question 3

Characteristics

Answer 3

-lower intelligence/IQ
-overly aggressive+lacking empathy-¨super male syndrome¨
-increased risk of developmental issues e.g ADHD+ austism
-taller than average
-curved pinky on right hand