Is there a genetic test for alcoholisim?

Yes and No. Genes have been identified which increase one's predisposition to alcoholism. Like many complex medical conditions, alcoholism is due to a combination of genes and environmental factors. Factors like life style, stress, exercise, and social support can have a large influence on whether someone with a predisposition actually becomes an alcoholic.
No. Alcoholism, like many behavioral conditions (depression, schizophrenia) exhibits multifactorial determination (combination of many genes plus the environment). There are markers for susceptibility to alcoholism, sometimes hyped as gene or protein profiling, but none validated for clinical use.