Genetic explanations of OCD

• A popular explanation for mental disorders is that they are inherited via genetics. Individuals inherit specific genes from their parents which are related to the concept of OCD
• The COMT gene

  The COMT gene is involved with the production of the neurotransmitter dopamine which has been implicated in OCD.

  • All COMT genes come in different alleles (forms), one form of the COMT gene has been found to be common in OCD partners.
  • This variation in the COMT gene produces lower activity on the COMT gene and higher levels of dopamine
  • This was demonstrated by Tukal et Al who tested 101 OCD patients and 100 healthy control ppts, those with OCD commonly had the variation of the COMT gene
• The SERT gene

  The SERT gene is also called 5-HTT and it effects the transport of serotonin creating lower levels of this neurotransmitter

  • A study by Ozakai et Al (2013) found a mutation of this gene in 2 unrelated families where 6 of the 7 family 👨‍👨‍👧 members had OCD
  • Low levels of serotonin can cause OCD as there is a reduction in the brain's ability to regulate mood and other mental processes
• Lewis (1936) observed that of his OCD patients, 37% had parents with OCD, 21% had siblings with OCD. This suggests that OCD runs in families, however, genetic vulnerability is passed on, not the certainty of OCD
• Diathesis stress model

  It is unlikely that there is a simple link 🖇️ between one gene and OCD. Genes such as the SERT gene are also implicated in other disorders such as depression and PTSD. The suggests that each individual gene 🧬 creates vulnerability (a diathesis) for OCD as well as other conditions. Other factors (stressors) affect what condition develops, or if one will develop. This explains why some people may possess the COMT or SERT gene 🧬 but do not have any mental illness