genetic explanations Flashcards
(8 cards)
Aubrey lewis 1936:
findings and what does it suggest?
- 37% had parents with OCD
- 21% had siblings with OCD
- suggests OCD runs in families
- genetic vulnerability
what is the diathesis-stress model?
certain genes make some people more likely to develop a mental disorder but it’s not certain
- environmental stress (experience) is necessary to trigger the condition
what are candidate genes?
- a gene that creates vulnerability for OCD
- some of these genes are involved in regulating the development of the serotonin system
what does it mean by OCD is polygenic?
OCD is not caused by one single gene but by a combination of genetic variations that together increase vulnerability
steven Tayloy 2013
- analysed previous studies that found evidence that up to 230 different genes may be involved in OCD
- dopamine and serotonin are both neurotransmitters believed to have a role in regulating mood
what is aetiologically heterogeneous?
origins of OCD vary from one person to another
- evidence to suggest that different types of OCD may be the result of particular genetic variations
LIMITATION; environmental risk factors
- OCD does not appear to be entirely genetic as there’s can also be environmental risk factors that can increase the risk of developing OCD
- Cromer et al 2007 over half the OCD clients in their sample had experienced a traumatic event in their past
- OCD was more severe in people with more trauma
- genetic vulnerability only provides a partial explanation for OCD
STRENGTH; Nestadt et al 2010
- strongly suggests that people are vulnerable to OCD as a result of their genetic makeup
- nestdat reviewed twin studies
- 68% of identical MZ shared OCD
- 31% of non-identical DZ twins
- family studies - a person with a family member diagnosed with OCD is around 4x more likely to develop it than someone without Marini and Stebnicki 2012