Alcoholism is a complex disease. It appears to run in families, yet it doesn't cause every member of a particular family to become an alcoholic. Not much is understood about exactly why a person decides to start drinking, or what factors cause that person to continue to drink despite negative repercussions. Ultimately, the result of having a drink differs widely from person to person. A new study shows that a gene variant may offer protection against alcoholism.
Some of the members of my family have alcoholism. I have always heard that if you have a parent or sibling who is an alcoholic that your chances of becoming one are increased. But, is this due to a genetic reaction to alcohol? Or is it because of environmental influences that were experienced by several family members? It's really difficult to tell.
It turns out that part of what causes a person to have alcoholism is genetic. There is a gene called CYP2E1. A variant on this gene plays a role in how a person responds to alcohol. People who have this gene variant have a very high sensitivity to alcohol. These are the people who experience inebriation after having just one or two drinks. The CYP2E1 gene is something that only around 10% to 20% of people have, and these people are less likely to become alcoholics than are people who do not have this particular gene variation. The CYP2E1 gene is a gene that encodes the enzyme that metabolizes alcohol, but it works in the brain, instead of in the liver where other genes that control the metabolism rate of alcohol are located.
In other words, it may be possible in the near future to use genetic screening to determine if you happen to have the CYP2E1 variant gene. This could be used to determine the risk a person has of becoming an alcoholic, before that person ever even tastes his or her first sip of an alcoholic drink.