Biological Explanation (Genetic)

Question 1

What are genetics?

Answer 1

DNA strands.

Question 2

What is the genetic assumptions of schizophrenia?

Answer 2

That genes cause schizophrenia. You can inherit these from family members. The closer the relative (1st degree/2nd degree etc) the higher the likelihood of development of SZ.

Question 3

What did Gottesman (1991) do in order to investigate the concordance rates of SZ?

Answer 3

A longitudinal family study with both DZ and MZ twins (62 people diagnosied with SZ) and compared likelihood of SZ.

Question 4

What are some of the findings of Gottesman (1991)?

Answer 4

If the following have SZ:
Aunt- 2% chance of developing
Sibling- 9% chance of developing
48% identical twin.

Question 5

What might be an issue with the twin studies in Gottesman (1991)?

Answer 5

Can’t separate out environment, purely correlational.

Question 6

Sz is polygenic- what does this mean?

Answer 6

That it appears there are several genes that may be involved in the development of Sz- not just one.

Question 7

How many separate genetic variations did Ripke (2014) find in his genome wide study?

Answer 7

108.

Question 8

What is a candidate gene and an example of one?

Answer 8

a gene that is believed to be related to a particular trait, such as a disease or a physical attribute (SZ in this case).
E.G PCM1

Question 9

What is aetioloogically hetereogenous?

Answer 9

Different studies have identified that different candidate genes which means that schizophrenia is aetiologically heterogeneous – i.e. a number of different combinations of genes can lead to the illness.

Question 10

What is the role of mutation in genetics?

Answer 10

SZ can also have a genetic component even without a family member having it- due to mutation.
E.G Parental DNA (fathers under 25 0.7% passing it on vs over 50 2%).
(BROWN 2005)

Question 11

A strength of the genetic explanation is research support from….

Answer 11

Gottesman

Question 12

However, a weakness of Gottesmans research is….

Answer 12

The concordance rates are not 100% so suggestive of other factors involved.
Environment/diathesis stress model etc.

Question 13

Practical application with the genetic explanation?

Answer 13

Genetic counselling- but the risk factor is an average figure and not usually accurate due to things like environment.

Question 14

A weakness of the genetic explanation is that it is reductionist… why?

Answer 14

It ignores other components such as hormones/trauma etc.