Alcoholism is genetic. Without the gene(s) anyone can have an alcohol problem but can recover from it without the syndrome.

Important point: the gene attenuates over time. The Chinese have had alcohol for 5000 years and almost no alcoholics. Societies most recently introduced to alcohol e.g. native Americans have very high levels.

Alcoholics have fewer kids.

My family has no alcoholics; we don't have the gene and nobody married into it. I started to realize growing up how lucky I am for that, seeing kids with belt-buckle scars because daddy likes his whiskey too much.