Genetic explanations for schizophrenia Flashcards
How are twins studies used?
Twin studies compare MZ twins to DZ twins to observe the differences. From this, you can observe whether characteristics are of nature or nurture. in schizophrenia, if one twin has it and it is genetic, the other MZ twin would have it, but the DZ twin would be less likely to have it.
Evaluate Twin Studies
Strengths- They are the most precise way of studying genetic inheritance.
There is a control over environmental factors.
Weaknesses- Identical twins can experience different environment, even in the womb.
MZ twins are usually treated as the same person, so their environment is not as controlled as previously thought.
Family History as a genetic basis
Less than a third of people with schizophrenia have a family history of it, suggesting a complexity in the genes. Chromosomal research suggests genetic evidence- 22q11 deficiency shows psychotic symptoms, and the frequency of this is 19%.
DISC1 genes are implicated in Tiwalis research.
DNA Pooling
This compares DNA from people with and without the disorder, to look at differences in allele frequency.
Copy number variation and Schizophrenia
Tiwari explains that given two-thirds of schizophrenia occurs sporadically, it is expected that more genes can come from variation (deletion, mutation and duplication).
Other factors related
Tiwari also explains other factors- Maternal infection, taking cannabis and epigenetic modification.
Evaluatory strengths for genetic explanation of schizophrenia
This is a reliable explanation as there are many different ways genes and variables are studied. DNA pooling, the close study of genetics, family studies and twin studies are used to support it.
The studies involved with this explanation are very generalisable, as they use large subject pool and are worldwide.
Evaluatory weaknesses for the genetic explanation of schizophrenia
This idea is far too complex- even though it indicates a genetic underpinning to the disorder, the explanation is too reductionist.
It is also reductionist in that is doesn’t take environmental factors into account.
