EXPLANATIONS FOR SCHIZOPH (FAMILY, ADOPTION, TWIN STUDIES) Flashcards
Can you summarise the genetic explanation for schizophrenia?
- Genetic explanation- suggests that schizophrenia has a heritable component.
- There are 3 ways of investigating genetic explanations for schizophrenia such as family, twin and adoption studies.
- Family studies- suggests that schizophrenia is more common among biological relatives, with higher risk for thoese closely related.
- Twin studies- suggests that there is a higher concordance rate for schizoprenia in MZ twins compared to DZ twins.
- Adoption studies- Individuals with biological schizophrenic parents are still at a higher risk, even if raised in non-schizophrenic families.
What is heritability?
A measure of how much of the difference in a trait (like intelligence or a disorder) between people is caused by genes, rather than the environment.
The extent to which variations in a trait (intellgience or a disorder) between people is caused by genes or enviroment
What are adoption studies?
A type of study that compares adopted children to their biological and adoptive parents to see whether a disorder is more linked to genes or the environment.
What are family studies?
A type of study that investigates whether a disorder runs in a family (is inherited)
What are twin studies?
- A type of study that compare the similarties and differences between MZ and DZ twins to understand role of genetics vs enviroment in developing certain disorders.
Concordance rate?
- The likelihood that family members or twins exhibit the same trait or condition.
Name 2 researcher that has investigated into concordance rates for schizophrenia using twin studies?
- Gottesman (1991)
- Hiker et al (2017)
What did Gottesman (1991) discover in regards to schizophrenia?
- Monozygotic twins (48%) have a higher concordance rate for schizophrenia than dizygotic twins (17%)
Demonstrates genetic component as MZ who share more fo their DNA are more likely to inherit the same disorder.
What did Hiker et al (2017) discover in regards to schizophrenia?
- Conducted a twin study with over 30,000 twin pairs in Denmark (using two national registers such the DTR and DPCRR).
- They investigated individuals with schizophrenia but also those with related disorders.
- They concluded that the heritability of schizophrenia was 79%.
How much ppts where in Hilker et al’s study?
30,000 Danish twins
What were the results of Hilker et al’s (2017) study?
- The heritability of schizophrenia was 79%
approximately 79% of the variation in the risk of developing schizophrenia can be attributed to genetic factors.
How did Hilker et al access his target population?
- Used two national registers
- Danish Twin Register (DTR)
- Danish Psychiatric Central Research Register (DPCRR)
