Biological Explanation 2: Addiction Genes Flashcards
What 2 genes are mainly associated with addictions?
DRD2
ADH
Explain DRD2’s role in addiction
Research has indicated a role for the D2 dopamine receptor gene (DRD2). Idv with the A1 variant of this gene have fewr dopamine receptors in areas which give her a sense of pleasure in response to normally adaptive behaviours. The lower amount of dopamine means the idv tries to overcompensate by overstimulation (addictions)
What did the research investigating smokers and the A1 varient of the DRD2 gene find?
That 48.7% of smokers and ex-smokers had the A1 varient compared to 25.9% of the general population
Explain the ADH genes role in addiction
Variations of these genes have been linked to an increased risk of alcholism. These individuals break down alcohol at a much slower rate meaning they are more likely to drink more and become addicted
How can ADH and ALDH decrease the risk of alcholism?
Some variants of these genes decrease the risk of alcoholism as it increases the levels of acetaldehyde in the body, which causes unpleasant reactions to alcohol, the variant is more common in Asian cultures
What are the ADH genes responsible for?
The ADH and ALDH genes are responsible for the process of how alcohol is metabolised by the body. AHD is an enzyme and breaks down alcohol into acetaldehyde then ALDH breaks it into water and acetic acid
What research has linked a specific variety of ADH genes to addiction?
Research has linked low activity variants of the ADH genes to an increased risk of alchol dependence in oriental cultures
Explain the evaluation point of the difference between the initation and matienence of an addiction?
Twin studies have been used to demonstrate the influence of genetic factors in addiction. Research which interviewed nearly 2000 twins found that, although enviroment and social factors influence initiation, addiction is highly dependant on genetic factors (dependece rate for coke was 35% for MZ and 0% for DZ twins)
Explain the evaluation point of is there specific gene for addiction?
The relationship between genetics and addiction is far more complex than one gene, DRD2, ADH and a number of others are idenified. As there are so many genes and so many different behaviours, it may be impossible to highlight which causes which
Explain the evaluation point of determinism (addiction genes)
Acceptance of genes as a sole explanation for addiction suggests that an addict has no choice andd cannont overcome it. Which may lead to them putting in less effort to recover as they believe it is gentic
Explain the evaluation point of the role of social and cultural factors in explaining addiction
Genetic explanations can be criticised as they ignore other factors. Such as changing social attitudes (e.g women born later , 1910 - 1958 , showed about 60% heritability to smoking)
What are the two main components of gentic factors in addiction?
Genes associated with addiction
The diathesis-stress model
Explain how the diathesis-stress model may provide a genetic explanation for addiction
It suggests that a disorder such as addiction only develops when a genetic predisposition is triggered by an environmental stressor. For example 5HTT has been linked to the development of alcholism if childhood maltreatment has occured.
