Genetics

Question 0

Cardno et al 98

Answer 0

Symptoms do different must be genes environment

Question 1

Kendler et al 85

Answer 1

18x with 1st relation
1% genpop
20% 1 parent
33-50% 2 parents

Question 2

Criticisms

Answer 2

Retrospective.
Shared environment
Concordance for MZs not 100%

Question 3

Copenhagen High Risk Study

Answer 3

Prospective.
207 children of schizos v 104 children of norms.
Age: 10-18.
Matched on age, gender, SES and urban/rural environment.
Followed up in 1974 and 1989.
16% in high risk group vs 1.9% in low risk group.
Supports familial link.
Supported by NY High Risk Project.
Cannot differentiate between genes and environment because of shared environment.

Question 4

Finnish Adoption Study - Tienari et al 2004

Answer 4

Adoption study.
National sample of adoptees.
So extensive kids were matched on demographic variables).
112 kids of schizos vs 135 kids of norms.
Separated before age of 4.
Families were ranked by psychiatrist on OPAS (33 sub scales of behaviours).
No bias by pharmaceutical funding.
Conducted over 30 years.
First follow up showed 1% vs 7%.
Schizos only came from dysfunctional/disturbed homes.
2004 follow up showed 5.8% vs 36.8% for healthy vs dysfunctional high risk group.
Levels of dysfunction and detrimental behaviours are not clearly defined and rating system is nonspecific.
Time point sampling doesn’t allow development to be observed.
Controversial as implies families are to blame.
Diathesis-stress model

Question 5

Conclusions

Answer 5

Some claim to found genetic markers others do not.
No one gene causes schizo.
Many of the common risk genes are found in genpop.
Complex combo of genre is required but unclear how genetic factors make contribution.