Biological explanations for schizophrenia
Genetic basis of schiz: inherited through genes, polygenic, candidate genes
Family studies confirmed the risk of schiz increases in line w/ genetic similarity
to a relative w schiz. Gottesman’s meta-analysis study found as genetic
similarity increases so does the probability of sharing schiz – aunt 2%, sibling
9%, identical twins 48%. Family members share aspects of their environment
as well as genes so correlation represents both but family studies still give
support for importance of genes in schiz.
Candidate genes – schizophrenia is polygenic (a no. of genes are involved).
Most likely genes would be those coding for neurotransmitters including
dopamine. Ripke found 108 separate genetic variations were associated w
increased risk of schiz. Therefore schiz is aetiologically heterogenous (diff
combo of factors) including genetic variation can lead to the condition.
Role of mutation. Schiz can have a genetic origin in the absence of a family
history of the disorder. One explanation for this is mutation in parental DNA
which can be caused by radiation or poison. Evidence for mutation comes from
positive correlations between paternal age and risk of schiz increasing from
around 0.7% w/ fathers under 25 to 2% in fathers over 50.
Ao3 of genetic base:
Strength is strong evidence. Family studies show risk increases w genetic
similarity to a family member w schiz. Adoption studies show biological kids of
parents w schiz are at a heightened risk even if grow up in an adoptive family.
This show some people more vulnerable to schiz as a result of their genetic
makeup.
Genetic basis of schiz: inherited through genes, polygenic, candidate genes
Family studies confirmed the risk of schiz increases in line w/ genetic similarity
to a relative w schiz. Gottesman’s meta-analysis study found as genetic
similarity increases so does the probability of sharing schiz – aunt 2%, sibling
9%, identical twins 48%. Family members share aspects of their environment
as well as genes so correlation represents both but family studies still give
support for importance of genes in schiz.
Candidate genes – schizophrenia is polygenic (a no. of genes are involved).
Most likely genes would be those coding for neurotransmitters including
dopamine. Ripke found 108 separate genetic variations were associated w
increased risk of schiz. Therefore schiz is aetiologically heterogenous (diff
combo of factors) including genetic variation can lead to the condition.
Role of mutation. Schiz can have a genetic origin in the absence of a family
history of the disorder. One explanation for this is mutation in parental DNA
which can be caused by radiation or poison. Evidence for mutation comes from
positive correlations between paternal age and risk of schiz increasing from
around 0.7% w/ fathers under 25 to 2% in fathers over 50.
Ao3 of genetic base:
Strength is strong evidence. Family studies show risk increases w genetic
similarity to a family member w schiz. Adoption studies show biological kids of
parents w schiz are at a heightened risk even if grow up in an adoptive family.
This show some people more vulnerable to schiz as a result of their genetic
makeup.
