Addiction (Addiction Genes) Flashcards
Is there a single gene responsible for addiction?
No, it’s unlikely; multiple genes likely increase susceptibility to addiction.
What is a major limitation of the dopamine theory of addiction?
It can’t explain individual variability in developing addiction.
Why do some people develop addiction while others don’t, despite similar exposure?
Genetic variations may make some individuals more prone to addiction.
What should we observe if addiction is genetic?
Addictive traits running in families.
What did Goldman et al. (2005) conclude about the heritability of addiction?
Addictions are moderately to highly heritable, with heritability ranging from +.39 to +.72.
How can inheritance studies help us understand addiction?
They investigate the role genes play by comparing rates among relatives or twins.
What did Prescott and Kendler (1999) find in their twin study on alcohol addiction?
MZ twins had higher concordance rates than DZ twins; 48–58% of alcohol addiction variance is genetic.
What did Kendler et al. (2012) find in their adoption study?
Children with biological relatives with drug addiction had a significantly higher risk of addiction, especially with environmental risk factors.
What did Agrawal and Lynskey (2008) conclude about genetic influence on addiction?
Genetic influence ranged from 30–70%, highlighting the importance of gene-environment interaction.
Which gene is associated with fewer dopamine receptors and addiction?
DRD2 (D2 Dopamine receptor gene).
How does the A1 variant of the DRD2 gene affect addiction risk?
It reduces dopamine receptors, increasing the likelihood of compensating via addictive behavior.
What did Comings et al. (1996) find about the A1 DRD2 variant?
41% of smokers had the A1 variant compared to 25.9% of the general population.
Which gene is linked to how the body metabolizes alcohol?
ADH and ALDH genes.
How do certain variants of ADH/ALDH genes affect alcohol consumption?
They increase acetaldehyde, causing unpleasant reactions like nausea and flushing.
Why do some East Asian populations drink less alcohol?
Unpleasant reactions due to genetic variants of ADH/ALDH discourage alcohol use.
How do other variants of alcohol-processing genes increase alcoholism risk?
They metabolize alcohol more slowly, allowing more drinking before negative effects are felt.
What is the diathesis-stress model in addiction?
Genetic predispositions are triggered by environmental stressors.
Why might identical twins not both develop addiction?
Because of differences in environmental exposure, even with the same genes.
What is a major limitation of twin studies in addiction research?
They may not fully separate genetic influence from shared environment.
What is a limitation of adoption studies?
Adopted environments still may not be entirely different from biological ones.
Why is studying specific drug addiction trends difficult?
People often use multiple substances and drug availability changes over time.
What did Regier et al. (1990) report about addiction and mental illness?
Addiction often co-occurs with mental disorders, complicating cause and effect.
What’s a challenge in studying the genetic basis of behavioral addictions?
It is understudied compared to substance addictions.
What percentage of people with antisocial behavior have substance abuse history?
84%.
Why is establishing cause and effect in addiction genetics challenging?
It’s unclear whether genes cause addiction directly or through another disorder.
What are some criticisms of the genetic explanation of addiction?
It is reductionist and may have gender and cultural bias.
What are some ethical concerns in genetic addiction research?
It may stigmatize individuals or suggest that change is beyond their control.
