By PT Staff, published on May 1, 1992 - last reviewed on January 23, 2015
Researchers have long known that alcoholism runs in families; in
fact, studies show that 60% of alcoholics have at least one alcoholic
parent. Yet whether the disease is caused by wayward genes or lost dreams
remains a mystery. Studies say both sides may be right.
Alcoholics, it is now clear are not all of one kind. Investigators
have found that, among men, there are at least two types -- those with
early-onset abuse (prior to age 25), and those whose illness sets in
later in life.
Researchers suspect that family incidence of alcoholism runs
unusually high among early-onset alcoholics, suggesting a genetic
predisposition. This group comprises 40% of the estimated million male
alcoholics in the United States. Impulsivity and violent behavior are
common among these men, who are motivated to seek alcohol is as a way to
By contrast, men who become alcoholics later in life have less
family involvement and use alcohol as a way to relieve anxiety and
stress. (Women problem drinkers are more in keeping with the late-onset
The possibility that genetic makeup predisposes some men to
alcoholism has sent scores of researchers scrambling to find the
chromosomal culprit. One group of studies implicates a gene that affects
the ability of brain cells to respond to dopamine--a neurochemical active
in pleasure responses. Unable to get enough dopamine because they lack a
sufficient number of receptors for it, the thinking goes, such people use
alcohol as self-medication in an attempt to boost dopamine levels.
But other researchers point to evidence of a "mean gene" that
impairs the action of serotonin, awide spread neurotransmitter that
normally dampens many brain stimuli, including those wrought by
So who's right? As researchers duke it out in the lab, Frederick K.
Goodwin, M.D., sees sense in the seemingly contradictory findings. What
it most likely means, says Goodwin, head of the National Institute of
Mental Health, is that there may be more than a single gene involved in
alcoholism, just as there is with diabetes. "There's no doubt it's a
Dr. Goodwin suspects that future research may even turn up a common
genetic predisposition to a complete host of addictions, including
alcohol and drugs--perhaps even extending to food and sex. Then, he
feels, yet another factor--genetic in some cases, perhaps environmental
in others--would influence the specific form of the addiction.