What is alcohol? What is an alcoholic? Why do some become addicted to it while others can drink as much as they want and not become dependent? What is an alcoholic? The answer to the first question and second questions seem fairly simple. Alcohol, by definition, is a flammable, volatile liquid produced by the fermentation of sugars and makes up the intoxicating constituent in spirits, beer, wine, and other drinks and an alcoholic is someone with an alcohol dependency. But, addiction’s genetic component plays an important role.
The answer to why do some people become addicted while others don’t is somewhat less clear. Society, in general, tends to think it is a matter of moral fiber or willpower, but it seems that the genetic cards we’re dealt play a greater role than either of those things.
Large scale studies have been conducted on twins and have provided strong evidence that among heritable mental illnesses, addiction ranks very highly according to Dr. David Goldman. Dr. Goldman is the head of the NIAAAA’s Laboratory of Neurogenetics. Genetics isn’t the only factor involved of course. Social influences and personal experience play a role as well. Addiction researchers have begun to piece together how genetic factors and specific experiences combined can pave the slippery path to addiction. There have been numerous genes linked to addiction, less than a dozen, however, have been implicated strongly.
Some genes appear to be substance specific; the genetic variation that affects the body’s metabolism of alcohol for example. Others relate to anxiety, personality, and mood disorders that are often found in those who seek stimulation or solace in drugs and/or alcohol. Some genetic patterns seem to be involved with more than a single type of addiction and may influence those pathways of the brain which are involved in the search for rewards.
“Our research supports other studies that indicate family and social environmental factors are influential in determining whether an individual begins using these drugs,” Dr. Kendler says about their study of more than 5,000 twin pairs. “But our findings suggest that the progression from the use of cocaine or marijuana to abuse or dependence was due largely to genetic factors.”
Even the tendency toward trying a dangerous drug such as heroin or crack is genetically influenced in part. For example, the particular area on chromosome 11 that is associated with seeking novel experiences and risk taking lies quite close to a region that have been associated with dependency. Researchers use study animals to measure how addictive a particular drug is. Hallucinogens and marijuana are the least habit-forming while opiates and cocaine are addictive enough that rats will often choose them over food.
Interestingly, research shows that the role played by genetics is directly proportionate to the addictiveness of the drug. For example, genetic strongly influence the likelihood that you will become addicted to crack, but the risk of becoming a pothead is more strongly influenced by social factors such as whether or not your friends use it.
It is well-known that the response to controlled substances varies greatly from person to person. Genetics are also responsible for many of these responses and it plays a large role in determining who becomes addicted and who doesn’t.
When it comes to how genetics affect an individual’s risk of becoming addicted, this is just the tip of the iceberg. There are many more factors involved and researchers are discovering new links every day. The answers to “what is alcohol?” and “what is an alcoholic?” will probably not change in the near future. The answer to “why do some people become addicted and others don’t” is changing daily as researchers delve further into the genetic components of addiction.