Genetics and Addiction: Is Alcoholism Hereditary or Genetic?

Is Alcohol Tolerance Inherited?

Alcohol tolerance means that equal amounts of alcohol lead to lesser effects over time, leading to a need for higher quantities of alcohol to feel the same desired effects.⁴ While it may seem like there is a genetic predisposition for alcohol tolerance, tolerance is not inherited.

It results from drinking substantial amounts of alcohol over long periods of time.⁵ However, alcohol intolerance may be genetic.⁶ Most commonly seen in those of Asian dissent, alcohol intolerance is when the body has an adverse reaction to the presence of alcohol. Most common examples is when a person’s skin flushes and nose gets stuffy right after drinking alcohol.⁶ This is a result of issues with alcohol metabolism, which is believed to be hereditary.⁶

Key definitions related to this topic include the following:

• Genetics. This is the study of how genes and their building blocks, DNA, contain sequences that determine the qualities and traits of a person. Each person has approximately 20,000 genes.²
• Heredity. This refers to the passage of characteristics and traits from parent to offspring through changes in DNA.²
• Genetic predisposition. This means that through a person’s genes and heredity they have an increased likelihood of having a certain disease, trait, or behavior.³ A predisposition doesn’t always cause a disease or trait to develop, but instead it tends to contribute to its development.³ Therefore, you may be predisposed to something and never actually have it develop.³
• Learned behavior. This is a behavior that developed from observing your surroundings or through direct experience. It is not heritable. Learned behavior can be learned through associating one stimulus with another (classical conditioning), in the early stages of life by imitating parents (imprinting), or by not responding to a stimulus after repetition (habituation).⁴

Can Alcoholism Skip a Generation?

There are many genes, and variations of genes, that impact a person’s risk of developing an alcohol use disorder.⁷ There is no one “alcohol gene” that leads to the development of an alcohol use disorder.^7,8 Researchers have found more than 400 locations in all the genetic information in an organism (genome) and at least 566 variants within these locations that could influence the extent that someone may suffer from alcohol abuse.⁹ Genes that relate to alcohol metabolism, particularly ADH1B and ALDH2, seem to be closest tied to the risk for problem drinking.⁷

A family history of alcohol use disorders may increase the risk of genetic predisposition to developing an alcohol use disorder, with risks heightened for parent-child transmission.⁸ Environmental factors also play a role in developing an alcohol use disorder when an individual has a family history of alcohol misuse. However, with multiple genes playing a role in the development of an AUD, it is possible that this disease could skip a generation. If parents do not have an alcohol use disorder, it does not mean that the offspring cannot develop an AUD.⁸ Similarly, if a grandparent has an alcohol problem but the parents don’t, that doesn’t mean a child won’t be predisposed to alcoholism.⁸

Can a Person Be Born with an Alcohol Use Disorder?

Because of the interaction of genetics and environment, a person cannot be born with an alcohol use disorder.¹⁰ Although people can have genes that predispose them to developing an alcohol use disorder, genetics only accounts for approximately half of a person’s overall risk.¹⁰ The rest of these predispositions comes from the social and environmental factors that a person encounters throughout their childhood and life.^7,10,

Tests for Alcoholism

A physician may use several tests to diagnose an AUD. These include:

• The Alcohol Use Disorders Identification Test (AUDIT).¹¹ This is a 10-item clinician-administered and self-report screening to assess alcohol consumption, drinking behaviors, and alcohol-related problems. Questions such as “How often do you have six or more drinks on one occasion?” are scored. A score of 8 or higher is considered to indicate hazardous or harmful alcohol use.¹¹
• The carbohydrate-deficient transferrin (CDT) test. The CDT is a blood test that detects biomarkers of excess alcohol use.¹³ It can potentially detect if someone is a binge drinker or a daily heavy drinker.¹²
• Electroencephalography (EEG). There is a diagnostic and screening tool that uses EEG to identify patients with possible AUD.¹³ Some researchers advocate for this to reduce the subjectivity of the AUDIT screening tool.¹³ Alcoholism-related EEG signals could enable physicians to make a more definitive diagnosis of AUD.¹³

Tips to Avoid Alcoholism When It Runs in the Family

If alcohol use disorders run in your family, you may want to be careful about your drinking or limit it. Remember that a combination of environmental factors and genetic predispositions lead to alcohol use disorders. So, there are various things you can control in your environment to try to avoid developing a problem. The Dietary Guidelines for Americans consider moderate drinking to be no more than 2 drinks for men and 1 for women per day.¹⁴ Staying within those limitations, or possibly avoiding alcohol intake altogether, may be a good idea.¹⁴ If you are a parent trying to prevent or delay your child’s alcohol use, some strategies include:¹⁵

• Sharing developmentally appropriate information and education about the dangers of alcohol use and your family history.
• Keeping track of how your child spends their time and recommending alcohol-free activities.
• Setting family rules that include abstaining from alcohol use.
• Helping your child develop skills like problem-solving, communication, and listening.
• Building your child’s confidence and sense of responsibility through youth leadership programs and the observation of older role models.

Take Our Alcohol Abuse Self-Assessment

Take our free, 5-minute alcohol abuse self-assessment below if you think you or someone you love might be struggling with substance abuse. The evaluation consists of 11 yes or no questions that are intended to be used as an informational tool to assess the severity and probability of a substance use disorder. The test is free, confidential, and no personal information is needed to receive the result.