Genetic explanations (OCD) Flashcards
What is genetics the study of?
genes and inheritance
What is OCD seen as?
a polygenic condition, where a number of genes are involved in its development
What does Family and twin studies suggest?
the involvement of genetic factors
Which gene appears to be mutated in individuals with OCD?
SERT gene (Serotonin Transporter)
What does the mutations cause?
an increase in transporter proteins at a neuron’s membrane.
This leads to an increase in the reuptake of serotonin into the neuron which decreases the level of serotonin in the synapse
What is the COMT gene responsible for?
regulates the function of dopamine
What does the mutation of the COMT cause?
the opposite effect as the SERT mutation
causes a decrease in the COMT activity and therefore a higher level of dopamine.
What did Carey and Gottesman (1981) find?
that identical twins showed a concordance rate of 87% for obsessive symptoms and features compared to 47% in fraternal twins. This difference suggests that genetic factors are moderately important.
What is the higher concordance rate for identical twins due to?
nurture as identical twins twins are likely to experience a more similar environment than fraternal twins twins since they tend to be treated the same.
Why are genes a limitation to determining who will develop OCD?
Genes only create vulnerability
Thus, they are not a direct cause as other factors must trigger the disorder. Evidence for this is that the concordance rates are not 100%, which shows that OCD is due to an interaction of genetic and other factors.
Why might OCD be culturally transmitted rather than genetically transmitted?
the family members may observe and imitate each other’s behavior, as predicted by social learning theory. Alternatively, family members might be more vulnerable to OCD because of the stressful environment rather than because of genetic factors.
