The sobering facts about alcoholism and genetics

Genetics and alcoholism are far more interconnected than originally thought, according to research.

The study, published in PLOS Genetics, provides evidence that no one gene is responsible for alcoholism, but rather hundreds. More than 900, to be exact.

Researchers located “signatures of selection,” or areas that indicated alcohol preference, and even discovered genes that were not first linked to alcoholism are now connected. These genes include those responsible for memory formation and reward behavior, which means treatment of alcoholism is much more complex than simply looking at one gene.

“Humans are relatively complex. Many traits are influenced by genetics,” says Dr. Brad Tinkle, medical director of clinical genetics at Advocate Children’s Hospital in Oak Lawn, Ill.

Obviously, there are other factors that influence alcohol consumption, which include, but are not limited to, social spheres, emotional health, family history and cultural expectations. But it isn’t easy for geneticists to determine exactly where the genetic influence and environmental factors meet.

“Some traits are fairly straightforward, like blue eyes, but things like scoliosis can include dozens to a few hundred genes that influence the occurrence, severity, progression and likely, the response to treatment,” says Dr. Tinkle. “Behaviors are likely more complex, and it is not unexpected that several hundred genes could be involved in behavior modification, response to various chemicals, drug metabolism, stress response, etc. While many may only have an incremental risk, there will likely be a few that have a stronger influence that will track in individual families. In my family alone, three of my mother’s siblings have died of alcoholism, and the other three virtually abstain, so the desire to start drinking is likely different than the ‘reward’ of drinking.”

According to the National Institute on Alcohol Abuse and Alcoholism, almost 88,000 people die each year in the US from alcohol-related causes. Alcohol remains one of the top preventable causes of death.

“We know all too well that family history of heart disease, dementia and addiction increases the risk to that individual, but often there is no ‘individual gene.’ What may be of greatest benefit of this study is looking at individual genes or the chemical pathways to see if medications may regulate this effect.”

Researchers say the findings suggest a possibility of pharmacological solutions, neurological-based or even genetic treatments may be in the future.

“What it means in the short-term is that while there is no genetic marker for alcoholism, a family history and co-morbid (concurrent) health conditions should heighten medical providers’, and everyone’s, sense that a person is at greater risk,” says Dr. Tinkle.