Risk Factors - Genetics Flashcards
What is genetic?
Refers to inherited characteristics that are passed from parents to their children in the form of information carried on their chromosomes.
What is a study based on genetics and gambling addiction?
Slutske (2010)
Interviewed 2,889 pairs of twins to investigate the role of genetic and environmental factors in the development of gambling addiction.
MZ twins had a higher rate of both twins being pathological gamblers (if one twin was a pathological gambler) than did DZ twins
Male MZ twins had a heritability estimate of 49% compared with 21% for male DZ twins.
For female MZ twins it was 55% compared with 21% for female DZ twins.
What is a study based on genetics and smoking?
Vink (2005)
Studied 1,572 Dutch twin pairs.
They found that, for both males and females, individual differences in smoking initiation were explained by genetic (44%) and environmental (56%) influences.
Also found that the likelihood of becoming addicted to nicotine was influenced primarily (75%) by genetic factors.
How does the dopamine receptor gene affect addiction?
Blum and Payne (1991) suggest that individuals who are vulnerable to drug addiction suffer from abnormally low levels of the neurotransmitter dopamine and a decreased ability to activate dopamine receptors in the reward centre of the brain.
This means that anything that increases the amount of dopamine can produce strong feelings of euphoria.
What did Sinha find? (2000)
A variant of the dopamine receptor gene associated with decreased dopamine receptor availability occurred with a much higher frequency in DNA samples of alcoholics compared to non-alcoholics
What are the evaluative points?
Gender differences in genetic vulnerability
Genetics and the diathesis-stress model
What is meant by gender differences in genetic vulnerability to addiction?
Research with women shows inconsistent findings regarding the role of genetic factors in alcohol addiction (McGue, 1997)
Only two of four adoption studies have reported a significant correlation between alcoholism in female adoptees and their biological parents.
This suggests that genetic factors may be less important in the development of alcoholism in women than in men
What is meant by genetics and the diathesis-stress model?
An advantage of genetic explanations is that they can explain why some people develop addictive behaviour, yet others who have the same experiences do not.
The A1 variant of the dopamine-receptor gene has been found to be associated with cocaine dependence (Noble, 1993) and nicotine dependence (Connor, 2007)
This suggests individuals who inherit this variant are more vulnerable to addictive behaviour because of low levels of dopamine and the increase in dopamine possible with drugs
