genetic vulnerability = the idea that someone may be more likely to become an addict because of their genetic make up

this does not mean that they will definitely develop an addiction but they are more likely to, given the right circumstances

some individuals may be born with a genetic vulnerability or a genetic predisposition to develop an addiction

circumstances = exposure to a substance or the opportunity within their environment to take it

a gene environment interaction is necessary to bring about the addictive behaviour

both male and female MZ twins were found to have much higher concordance rates compared to DZ twin pairs

studied 2889 pairs of twins to investigate the role of genetic and environmental factors in the development of gambling addiction

this suggests there is a genetic component to gambling that can be present in both men and women

environmental factors are also likely to be involved, especially as concordance rates amongst MZ twins were not 100%

research suggests that there is a specific gene involved in addiction

occurred with a much higher frequency in the DNA of samples taken from alcoholics compared to non alcoholics

reported that a particular variant (A1) of the dopamine receptor (DRD2) gene is associated with fewer dopamine receptor sites

individuals with this gene may not receive enough simulation from everyday activities. individuals continue to engage in addictive in behaviours