Clinical

Question 1

What is evidence supporting genetics as an SZ explanation

Answer 1

Hiker et al - heritability of sz is 79
meaning 79% of individual differences that we see in sz is due to genetic differences
( comt gene and disc1 gene)

Question 2

What is the comt gene

Answer 2

codes for an enzyme that breaks down dopamine in the pfc, deleting this gene means unregulated dopamine levels meaning there are sz symptoms

Question 3

what is the Disc1 gene

Answer 3

people with an abnormal disc1 gene are 1.4x more likely to develop sz, as it coded for gaba (NS) which regulates dopamine and glutamate in limbic system

Question 4

a weakness for biological explanation of sz

Answer 4

Research to support
Gottesman analysed concordance rate for people w diff genetic similarity. Clear link between genetic similarity and an increase in two related individuals having sz. MZ had a 48% concordance whereas parents and children had 9%
Shows Sz is not entirely genetic but plays a sig part

Question 5

Counter to Gottesman research on genetics

Answer 5

MZ are treated more similar than DZ so similar living experience, expanding the concordance MZ display

Question 6

Weakness for bio explanation for sz

Answer 6

concordance rate is far from 100%, even for MZ twins
Research demonstrated the longer a person had been exposed to city life and the denser the pop, the greater risk of sz, suggesting that living rurally may protect someone developing a disorder they are genetically predisposed to
Shows one way that environment can affect how it is possible for MZ to differ in terms of onset sz

Question 7

Another strength for bio explanation
( hint: candidate genes)

Answer 7

research for candidate genes for sz
a review of 14 studies concluded disc1 is associated with presynaptic dopamine dysregulation
egan et al proposed a link between decreased dopamine in pfc and one form of comt
genes cause neurochem differences predisposing someone to sz

Question 8

weakness for bio explanation
hint: correlation not causation.

Answer 8

genetic factors may serve as risks or vulnerabilities to sz rather than a strict causes, this is seen in the diathesis stress model
diatheses- genetics stress- life experience
houston et al found harsh parents and abuse can increase rates of sz and cannabis use