There is a proven genetic disposition, susceptibility, whatever you want to call it. It is proven to run in families and it is proven that some backgrounds such as American Indian are genetically predisposed.
So there's no arguing with that.
However the question seems to be here--does having this condition excuse bad behavior?
I think not based on the logical argument that not all drunks go home and beat their families, or any other bad behavior. If the behaviors were caused by the disease, then all alcoholics would behave exactly the same--either all would beat their families or none would.
Not to say that many don't have similar behaviors. It's amazing how similarly they can think. It's also good to point out that there are as different types of alcoholics as there are anything else.
Not arguable: Alcohol is a poison. Not arguable: That poison in large quantities will destroy the liver and other organs. Not arguable: Those who drink excessively, disease or not, mess up their lives.