Family use of Marijuana:

There is a study being down that examines he familial aggregation of marijuana use, abuse, and dependence.  During the experiment, 2,546 individuals from 781 families were interviewed and the risk factors were calculated for each situation, and the data showed that for all three areas, the risk ratios were elevated in the family members of clinical pro bands. Meaning that the risk factor is transferrable from parent to offspring. This shows how some people are more prone to the addictive qualities of marijuana than others based off of their genetics passed down to them from their parents.