I think there is a genetic predisposition to alcoholism, but environmental factors provide the tipping point. It is not an either or relationship. Will power is important, but if we had will power there would not be so much obesity in the population. I am not trying to give people an excuse but, you do see it in certain families and populations. IQ is also somewhat genetic, but without the proper nutrition, it could be decreased. There are many genetic factors that are expressed in human behavior as the human genome is decoded, I am certain there will be many more interesting relationships between negative and positive behavior and genes. It will be a Brave New World.