ALCOHOLISM AND GENETIC FACTORS: STUDIES OF NONALCOHOLIC BLOOD RELATIVES
These studies_ are sometimes referred to as studies of persons at high risk, and are similar to the genetic marker studies. Any genetic difference between those who are biologically prone to alcoholism and those who are not will, as noted, be manifested in some biochemical differences. Efforts are underway to see what factors may distinguish between these two groups. The major hypotheses are that there may be differences in the way our bodies handle alcohol and our brains experience its effects. The differences could conceivably be differences of metabolism, or differences in response to chronic exposure to ethanol, or possibly a unique response to a single dose (e.g., those at high risk having greater pleasure and those at low risk more discomfort).
What does the research to date show? There does seem to be a difference in metabolism. In one study, a group of presently nonalcoholic young men with an alcoholic father or brother showed greater acetaldehyde levels during alcohol metabolism than another similar group who did not have an alcoholic family member. Much higher levels of acetaldehyde often accompanies drinking in Orientals. At these higher levels it produces an Ant abuse-like reaction, which discourages alcohol consumption and thereby provides protection against the development of alcoholism. Paradoxically though, with a modest increase of acetaldehyde, the addiction process may be facilitated. Another preliminary study has looked at how alcohol's effects are experienced, again using young men who exhibit no symptoms of alcoholism but have an alcoholic blood relative. Those having an alcoholic family member describe a lesser response to a single dose of alcohol than those with no alcoholic blood relative. To translate this, those with a family history of alcoholism didn't feel as "high" as did those without alcoholism in the family. Other researchers have determined that those with a family history of alcoholism have greater muscle relaxation with a single dose of alcohol than those without a family background. After drinking, those at "high risk" also have been reported to have more brain alpha wave activity, as measured by electroencephalogram (EEG). And among the more interesting findings, "high-risk" subjects perform more poorly on portions of standard neuropsychological tests that measure brain function. This finding is interesting because it has long been recognized that alcoholics do poorly on such tests. This diminished performance had always been presumed to be the result of brain damage from heavy drinking. Now the question has to be asked whether this condition predates the alcoholism.
Most research initially discussed the differences described above as deficiencies, as something "missing" or "lacking." It is now being recognized that what is inherited may not necessarily be a deficiency but might, paradoxically, be viewed as a "strength." In other words, some people might inherit an ability to handle alcohol "too well." They may be more immune to negative physical consequences of drinking such as nausea and hangovers, or be able to function better than the average person when alcohol is ingested. This perspective may be useful in client education.
