Biological Explanation: Genetic Basis Of Schizophrenia

Question 1

What is the genetic basis of schizophrenia?

Answer 1

1. The higher the genetic similarity, the higher the concordance rate.
2. SZ is polygenic - caused by multiple genes.
3. SZ is aetiologically heterogeneous- different genetic variations cause the disorder.

Question 2

Outline twin research into schizophrenia.

Answer 2

Gottesman: conducted a meta analysis and found MZ twins had a concordance rate of 48% compared to DZ twins who had a concordance rate of 17%.
Concluded that the higher the genetic similarity, the higher the concordance rate.

Question 3

Outline research which suggests schizophrenia is aetiologically heterogeneous.

Answer 3

Early research attempted to find candidate genes however, SZ is aetiologically heterogeneous.
Ripke et al: studied 37,000 patients and found 108 separate genetic variations that cause SZ.

Question 4

Outline adoption research which suggests schizophrenia has a genetic vulnerability.

Answer 4

Tienari et al: adoption study, compared control group to adopted children whose biological mothers had SZ - found that 6.3% of those with a SZ mum went on to develop SZ and 2% of control developed SZ.

Question 5

Outline research which shows schizophrenia is caused by candidate genes.

Answer 5

Seker et al: studied 65,000 people and found C4 gene resulted in a higher risk of developing SZ

Question 6

What are two strengths of the genetic basis of schizophrenia?

Answer 6

1. Can lead to the prevention of SZ developing or, getting worse.
   Gene mapping can be used to monitor development of SZ.
   Gene mapping is where the location of genes implicated in SZ are identified.
   Shows SZ can be identified at an early stage which can prevent it from spiralling out of control.
   Therefore, bio explanation has real life application.
2. Evidence for genetic vulnerability.
   Adoption studies such as Tienari et al show that the environment plays little to no role in development of SZ.
   Shows genetic factors play key role in SZ.
   Therefore, genetic makeup can determine SZ.

Question 7

What is one weakness of the genetic basis of schizophrenia?

Answer 7

1. Biologically deterministic.
   Explanation assumes SZ is inevitable as, genetic vulnerability is innate which suggests ppl have no control over SZ.
   May make sufferers feel disempowered.
   Psychological approaches may be more useful - acknowledge free will which can manage disorder.
   Therefore, expl offers a narrow viewpoint of SZ and ignore free will and the influence of this on SZ.