Risk Factors and Addiction- Genetic Influence Flashcards
How do genetics influence addiction?
- Pathological gamblers may inherit a faulty A1 DRD2 gene which reduces the number of dopamine receptors in our pleasure centres within the limbic system, so individuals with this variant are less sensitive to rewards and may seek out extra stimulating activities like gambling to compensate (Comings et al)
- 69% of a sample of alcohol dependent users and a 51% sample of cocaine dependent users had this genetic variant (Blum et al)
If the point is:
A strength of genetics as a risk factor is that there is evidence to show how they’re involved in many addictions.
What is the evidence and link?
Evidence- Using an adoption study, Shields et al examined the concordance between 42 twin pairs that were reared apart. Only 9 pairs were actually discordant, showing how genetic similarity is a major factor in starting to smoke. Results of a twin study by Shah et al using adults found strong evidence of genetic transmission in men.
Link- This suggests that the explanations of genetics has more reliability due to its support.
If the point is:
A weakness of genetics as a risk factor is that, despite the need for general nomothetic laws, the role of genetics in addiction is overly deterministic.
What is the explanation, evidence and link?
Explanation- It implies that we have no free will and if we happen to possess any of the faulty genetic traits we are destined to be an addict for life.
Evidence- This is clearly not the case, as illustrated by Blum et al and the A1 DRD2 variant. This genetic variant isn’t present in all cases of addictions and is common in up to 20% of the ‘normal’ population as well as those suffering from OCD and Tourette’s syndrome.
Link- This means that genetic risk factors are not exclusive to addictive behaviours.
What are the evaluation points for genetics as a risk factor?
+ Evidence to show that genetics are involved in many addictions
— Findings from research linking genetics to addiction can be easily explained using nurture and environmental influences
+ For a more comprehensive view of risk factors and addiction, genetic factors can be used as part of the diathesis stress account
— Despite the need for general nomothetic laws, the role of genetics in addiction is overly deterministic
If the point is:
A weakness of genetic influences as an explanation of addiction is that findings from research linking genetics to addiction can be easily explained using nurture and environmental influences.
What is the explanation, evidence and link?
Explanation- It also highlights the importance of environmental factors, as the concordance rate for monozygotic twins in all studies was under 100%, so the studies make the assumption that twins share exactly the same environment but monozygotic twins are treated more similarly by their environment than dizygotic twins. The transfer of individual abilities, traits, behaviour and outcomes from parents to their children (inter generational and transmission) may be responsible for some addictions.
Evidence- For example, if a parent is addicted to smoking, the child may become addicted later in life due to the environment they grew up in, normalising this behaviour.
Link- This means that the role of genetics in addiction could be considered to be reductionist, as it fails to recognise environmental factors, such as upbringing, in addiction.
If the point is:
A strength of genetic influences as an explanation of addiction is that, for a more comprehensive view of risk factors and addiction, genetic factors can be used as part of the diathesis stress account.
What is the explanation and link?
Explanations- It has been suggested that pathological gamblers may inherit a faulty A1DRD2 gene (Comings et al) that reduces the amount of dopamine in the pleasure centres in the limbic system. This generic vulnerability is the diathesis contributing to addictions. However, research has found that people exposed to severe stress are more vulnerable to addictions, especially children who may have experienced parental loss or child abuse. This is the stress that could trigger the genetic vulnerability.
Link- This means that this risk factor is a more comprehensive view, making it much more credible and useful.
