biological explanations - genetics ao1

Question 1

what are the 2 types of twins called?

Answer 1

1. monozygotic = identical == 1 fertalised egg splits and develops 2 babies with exactly the same genetic info
2. dizygotic = faternal

Question 2

how are family studies used?

Answer 2

find individuals who have schiz and see whether their biological relatives are more affected than non-biological relatives

Question 3

Gottesman 1991

Answer 3

• MZ twins = 48% risk of getting schizophrenia
• DZ twins = 27%
• higher the degree of genetic relativeness the higher the risk of getting schizophrenia

Question 4

benzel et al 2007

Answer 4

COMT , DRD4 , AKT1 = excess dopamine in specific D2 receptors
- leading to acute episodes, positive symptoms (delusions, hallucinations, and strange attitudes)

Question 5

2 studies = closer the biological relationship, the greater the risk of developing schizophrenia

Answer 5

• Kendler (1985) = first-degree relatives of those with schizophrenia are 18 times more at risk than the general population.
• Gottesman (1991) = schizophrenia is more common in the biological relatives of a schizophrenic, and the closer the degree of genetic relatedness, the greater the risk.