Schizophrenia: One other biological explanation

Question 1

What did Hilker et al. suggest?

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Answer 1

• 79% heritability rate for schizo

Question 2

How may a gene mutate?

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Answer 2

• Environmental factor

- Error during cell division (deletion/duplication of strand of DNA)

Question 3

What is DiGeorge Syndrome caused by and what % of people go on to develop schizophrenia from it?
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Answer 3

• Deletion of COMPT gene

- 25% of people

Question 4

What is the role of the COMT gene? (candidate gene)

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Answer 4

• Instructions to create enzyme breaks down NT’s in prefrontal cortex

Question 5

How may COMT gene cause schizophrenia?

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Answer 5

• Deletion of it = dopa lvls poorly regulated

Question 6

What did Kim et al. (2012) mention?

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Answer 6

• Abnormality to DISC-1 gene = 1.4x ^likely to develop schizo

Question 7

What is the role of the DISC-1 gene? (candidate gene)

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Answer 7

• Codes for creation of GABA (NT that regulates other NT’s in limbic system)

Question 8

What does the diathesis stress model suggest?

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Answer 8

• Genes = vulnerability for schizo
• Possess schizo genes (diathesis)
• Only triggered by other bio/environmental effects (stressors)

Question 9

Evaluate genetics as an explanation of schizophrenia

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Answer 9

Gottesman found clear relationship between gen similarity and ^in 2 related individuals having schizo. Gottesman and Shields found concordance rates of 42% (MZ) and 9% (DZ)

Pederson and Mortensen showed the longer a person has been exposed to city life, denser pop, ^risk of schizo. Rural dwelling protect person from a disorder they’re genetically predisposed to

Dahoun et al. said DISC1 associated w pre synaptic dopa dysregulation (schizo). Egan et al. said link between >dopa activity in prefrontal cortex and form of COMPT gene. Inheriting 2 copies of the Val allele ^risk of schizo by 50%

Question 10

What is meant by epigenetics?

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Answer 10

• Stressors change way gen code is expressed and gen vulnerability may be switched on