genetic risk factor

Question 1

how does genetic become a risk factor for addiction?

Answer 1

• A specific addiction cannot be inherited. For example, it makes no sense that an addiction to phone use is inherited as they have only been a part of our lives very recently.
• What is inherited is a vulnerability to drug dependence. These individuals may be predisposed to feel the sensations of the drugs with more intensity and thus, they are more likely to become addicted to its effects.
• Any genetic explanation needs reference to specific candidate genes.
  Here, A1DRD2 gene has been implicated by Comings et al (1996). This gene reduces the number of dopamine receptors are reduced in someone’s brain, meaning they have to go out and try achieve extra stimulation (hence, drugs and alcohol).
• …Studies have shown genetic component for various addictions, eg alcohol, nicotine; genetic factors influence the number of dopamine receptors and activity of enzymes responsible for metabolism of addictive processes, eg alcohol; indirect genetic effects on mediating factors, eg personality traits, IQ etc”

Question 2

what is some evidence for genetics as a risk factor for addiction?

Answer 2

• Using an adoption study, Shields et al (1962) 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.
• Shah et al (2005) used adults to find strong evidence of genetic transmission in men. Black et al (2006) also found that 1st degree relatives of gambling addicts were much more likely to suffer the same fate as more distant relatives

Question 3

what are some positive evaluations for genetics as a risk factor?

Answer 3

• P - One strength of genetics as a risk factor for addiction is that there is research to support it. E - For example, Using an adoption study, Shields et al (1962) 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. E - This highlights that there must be a genetic component to the development of an addiction , L - increasing the credibility of genetics as a risk factor.
• P - One positive of genetics as an explanation of why we develop addiction is that it has practical applications. E - By understanding genes are a vulnerability, we can identify what triggers these genes and get individuals to avoid these triggers. E - Further, this can be objectively measured using genetic testing to understand who may have a vulnerability to developing an addiction and therefore provide extra support to those individuals. L - This means that research into genetics has enabled us to identify those who may be at risk of developing addictions before they start, making it a useful explanation.

Question 4

what are some negative evaluations for genetics as a risk factor?

Answer 4

• P - One weakness of the genetic explanation as to why someone may develop an addiction is that it suffers from biological reductionism.
  E - The genetic explanation fails to take into account other factors that could potentially also increase the risk of someone developing an addiction. E - Furthermore, we know from research such as Shields et al (1962) that there is not an 100% concordance rate between twins reared apart, therefore there must be other factors that contribute to the development of an addiction. L - Therefore it is theoretically reductionist and unlikely to be the whole explanation
• P - One weakness of genetics as an explanation for addiction is that it is biologically deterministic
  E - This explanation assumes that if someone has a gene that causes addiction, that they will most likely develop an addiction at some point in their life. It doesn’t consider the element of free will, and that people may actively resist addictive behaviours, particularly if they have seen a family member struggle with addiction as well. E - Furthermore, it provides little comfort to people who have a genetic vulnerability as the explanation makes it seem inevitable that the person will then develop an addiction. L - Therefore it is socially insensitive as it suggests that people with addictions were also destined to be addicts.
• Finally, no genetic explanation can find a 100% concordance rate.
  For example , although Kendler et al (1997) – found the concordance rates in MZ twins higher than DZ twins with alcohol addiction, there was still not an 100% concordance rate.
  Therefore, it is likely that the environment plays a role, meaning the genetic explanation has lowered explanatory power. It is also incredibly unlikely that an individual will get addicted to a substance that they have never been exposed to, so the environment clearly does play a part in this.