One Biological Explanation for Alcohol Addiction - DRD2 Gene

Question 1

What does the DRD2 genetic explanation argue about the risk of drug addiction?

Answer 1

Argue that the risk for drug addiction is inherited

Question 2

What does the DRD2 genetic explanation argue dopamine neurotransmission is involved in?

Answer 2

Genes of the dopamine system harbour risk varients, as dopamine neurotransmission is involved in mediating the rewarding effects of drugs of abuse

Question 3

Where is dopamine released?

DRD2 genetic explanation

Answer 3

Released in the mesolimbic dopamine system of the brain to signal reward and pleasure

Question 4

What does dopamine bind to?

Answer 4

Dopamine binds with receptors in the brain

Question 5

Where are many D2 dopamine receptors found?

Answer 5

Many D2 dopamine receptors found in the ventral tegmental area (VTA) and the nucleus accumbens

Question 6

What is the DRD2 gene viewed as?

Answer 6

Viewed as a pleasure seeking gene and codes for the number of D2 dopamine receptors available in the mesolimbic dopamine system

Question 7

What do people with the A1 variant of DRD2 have less of?

Answer 7

Have less dopamine receptors meaning they are unable to feel pleasure and satisfaction as well as someone with higher number of dopamine receptors resulting in a ‘reward deficiency’

Question 8

What do researchers speculate about individuals with the A1 variant of DRD2?

Answer 8

Speculate they pursue pleasure seeking behaviour such as using alcohol in a way to stimulate their existing dopamine receptors giving them pleasure levels comparable to people with a standard number of receptors

Question 9

What percentage of the A1 variant has been found in alcoholics compared to non-alcoholics?

Answer 9

A1 variant has been found in 42% of alcohols compared to 25% of non-alcoholics

Question 10

What is the supporting evidence of the A1 varient of DRD2 genetic explanation?

Answer 10

Noble (1996)

Connor et al (2002)

Diathesis-stress model

Question 11

What are the weaknesses of the A1 varient of DRD2 gene as an explanation for alcohol addiction?

Answer 11

Collaborative study on the genetic of alcoholism in 1998

Usefulness

Reductionism

Nature-nurture debate

Question 12

Why is Noble (1996) supporting evidence for the DRD2 gene as an explanation for alcohol addiction?

Answer 12

Found that when dopamine is stimulated by dopamine receptor agonists, alcohol consumption reduces whereas dopamine receptor antagonists which decrease dopamine levels increased alcohol consumption therefore showing a clear link between number of dopamine receptors and alcohol consumption

Question 13

Why is Connor et al (2002) supporting evidence for the DRD2 gene as an explanation for alcohol addiction?

Answer 13

Studied a sample of adults from an alcohol detoxification unit

A clinical interview and the alcohol dependence scale (ADS) questionnaire were used to collect data and found that individuals with A1 variant consumed larger quantities of alcohol and had earlier age of onset for alcohol related problems

Question 14

Why is diathesis-stress model a strength for the DRD2 gene as an explanation for alcohol addiction?

Answer 14

A1 variant found in 25% of general population who don’t have an addiction to alcohol suggesting presence of gene alone doesn’t cause alcoholism

Likely to be adequately explained by adopting diathesis-stress model for behaviour which assets interaction between diathesis and stress serves as best predictor of eventual onset of addictive behaviour such as alcoholism

Question 15

Why is Collaborative Study on the Genetics of Alcoholism in 1998 a weakness for the DRD2 gene as an explanation for alcohol addiction?

Answer 15

Analysis of 105 families

Involvement of DRD2 in alcoholism was not found to be significant

Concluded that there is no single “gene for alcoholism” but rather variations in many different genes that together, interacting with the environment, place some people at significantly higher risk for the diseases

Question 16

Why is usefulness a weakness for the DRD2 gene as an explanation for alcohol addiction?

Answer 16

Doesn’t explain why someone first starts using a drug before the development of any physical addiction

Learning explanations may be more appropriate

Biological explanations cannot be considered a full explanation for addiction

Question 17

Why is nature-nurture debate a weakness for the DRD2 gene as an explanation for alcohol addiction?

Answer 17

Takes on the nature side of nature-nurture debate, it argues drug misuse is die to physiological changes in the brain

Learning approach takes nurture side of debate because it argues drug misuse is due to environmental factors such as reinforcement and imitation

Question 18

Why is reductionism a weakness for the DRD2 gene as an explanation for alcohol addiction?

Answer 18

Biological explanations for drug misuse such as DRD2 pinpointed a specific variant of a gene

Can be viewed as reductionist approach as drug taking is a behaviour that occurs within a social context, with other drug users etc.

Biological explanation tend to ignore contextual effects on drug taking and experiences