Genetic explanations

• COMT gene: 


  may contribute to OCD. It is involved in the production of catechol-O-methyltransferase and regulates production of neurotransmitters dopamine.

  One form of the gene has been found more common in OCD patients without activity levels of COMT gene and higher levels of dopamine.
• The SERT gene:


  Affects the transport of the serotonin, lower levels are created of this neurotransmitter.

  These lower levels are also implicated in OCD patients.
• Diathesis- stress


  -idea of a simple link between one gene and a complex disorder.

  -It creates vulnerability for OCD.

  -Stressors' affect what condition is developed or if the mental disorder is developed.

  -People can posses the COMT or SERT gene but not be a sufferer of OCD.
• Evaluation of genetic explanations:


  -There is good supporting evidence: Neustadt et al reviewed twin studies and found that 68% of identical twins share OCD compared to 31% of non-identical twins.

  -Environment or genetics:

  problem with twins as they have the same families as well as having similar genetic material so unclear whether OCD is caused by genetics or environment.

  -Environmental risk factors:

  triggers or increase risk of OCD, Cromer et al found over half the OCD patients had trauma from past and OCD was more severe in those with more trauma.