- Genetically decreased CYP2A6 and the risk of tobacco dependence: a prospective study of novice smokers. O'Loughlin, J., Paradis, G., Kim, W., DiFranza, J., Meshefedjian, G., McMillan-Davey, E., Wong, S., Hanley, J., Tyndale, R.F. Tobacco control. (2004)