SCH - genetic explanation

Question 1

what are the genetic explanations to schiz

Answer 1

• inheritance
• adoption studies
• specific genes
• birth complications
• cannabis
• childhood trauma

Question 2

how do family studies explain inheritance for schiz

Answer 2

• seems to run in families
  GOTTESMAN 1978
• rate in the world is 1%
• having a first degree relative with schiz = 12%
• both parents = 40% chance
• reviewed by Tsuang and stated similar findings

Question 3

strengths and weakness of Gottesman’s family study

Answer 3

+ve: suggests bio cause so can intervene early, provide meds
-ve: ignores role of environment, interactionist - genes + stress = schiz

Question 4

how do twin studies explain inheritance of schiz

Answer 4

GOTTESMAN AND SHIELDS 1966:
- primary data, read hospital notes (secondary)
- gathered qualitative and quantitative
- longitudinal -> allows each twin the chance for schiz to show
FOUND: severe schiz and MZs had a 75% concordance, 22% for DZs

Question 5

what followed up Gottesman and Shields

Answer 5

literature review
1967: adoption/twin studies found concordance rates for mild schiz was 42% for MZs
HILKER 2018:
found concordance for mild schiz was MZs BUT more modern so could be due to better meds, support or early intervention

Question 6

who studied adoption for schiz

Answer 6

Tienari - shows that biological children of parents with schiz are at heightened risk if they are adopted
- STRESS: traumatic life experiences early on
- Identity crisis: delusions of who you are

Question 7

how are specific genes applied to schiz

Answer 7

it is thought to be polygenic (100-700) - little predictive power
- candidate genes : term given to genes that have been implicated in development of schiz
- associated with increased risk as they are responsible for function of neurotransmitters

Question 8

who studied specific genes

Answer 8

Ripke 2014
- studied data from genomes
- 37,000 schiz patients, 113,000 controls
- concluded 108 genes were associated with schiz risk
- mostly worked on dopamine

Question 9

what are 2 examples of genes

Answer 9

COMT - corrupted
involved with dopamine receptors - leads to HYPERdominergia
DISC-1
- DELETION of an important gene which has been associated with schiz (unsure which gene)

Question 10

what are some other causes of schiz

Answer 10

• birth complications
• cannabis
• childhood trauma

Question 11

LIMITATION of genetic explanation

Answer 11

family studies ignore the role of the environment (Gottesmann)
reductionism
requires further explanation - focus is only on genetics