Some people use drugs and others do not. Some people suffer from addiction and others do not. Surprisingly, these two groups are not mutually exclusive. Since not everyone who uses drugs suffers from addiction, we can rule out the drugs themselves as being the cause of addiction.
Causes of addiction vary widely, but the real question is why do people become addicted in the first place? It’s similar to gaining weight. One person can consume junk food all day long and not gain weight, while another who consumes half as much, gains weight immediately. We tend to blame it on genetics, but is that really how genetics works?
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How Do Genetics Work?
Most people understand that you inherit all of your physical and personality characteristics from your parents. You are made up of some random combination of genetic material borrowed from each of your parents. They, in turn, are unique combinations of their parents, and so on.
Based on the number of genes each person carries, and the fact that they randomly combine during reproduction, there are 8,388,608 possible genetic combinations possible from each parental pair. That means you and your siblings, although you come from the same parents, can vary greatly in genetic characteristics.
Your genetics contain the blueprint for your life. They determine the color of your eyes and hair, the shape and size of your ears and nose, and everything else about you. The unique combination of genetics you inherited is what makes you, you.
Your genes came in pairs from your parents. You eye color, for instance, is determined by a combination of four genes: Two from your father and two from your mother. If you got two blue eye genes from your mother and two brown eye genes from your father, your eyes are probably brown. Brown eye genes are dominant, so, when balanced equally with blue eye genes, the brown ones win.
Predicting eye color becomes more complicated when you consider there are genes that are carried but not expressed. A man with blue eyes may carry a gene for green eyes he inherited from his mother. If it is the green eye gene that ends up in his child, and the child’s mother contributed only blue eye genes, the child may have green eyes. Blue eye genes do not override green ones, and although green eyes were not visible, the gene was present and handed down to the child.
With such a large combination of genes possible in each person, it is easy to see why it has taken decades for scientists to map genetic code. Eye color is a rather simple genetic matter, but many other characteristics are far more complicated at the genetic level.
Genetic Components of Addiction
The genetics of addiction are extremely complex and not yet fully understood. There is more than one gene responsible for addiction, so it’s not as easy as either “having it” or “not having it.” In fact, all humans are hardwired for potential addiction.
A natural part of your brain is the ability to experience pleasure. This is a natural ability designed to reward you for performing necessary functions, such as eating. When you do something that is pleasurable, your brain remembers that feeling and strives to experience it again.
There are certain substances that trigger your natural reward system more profoundly than others. Cocaine, for example, floods your brain with more feel-good chemicals than it could ever produce on its own. The intensity of the pleasure it creates accelerates the reward cycle exponentially. Your desire to experience the cocaine high again quickly becomes so strong you cannot resist. That is the addiction that can happen to anyone.
The genetic makeup of each individual can also accelerate the addiction cycle — or, it may slow the development of addiction. Evidence of the discrepancy is clear in these use and addiction statistics. 2 billion people, according to a World Health Organization study in 2004, drink alcohol, but only 76.3 million have an alcohol use disorder.
The genetic pre-disposition to addiction works the same way as eye color. There may be no visible evidence that you are more susceptible to addiction than others. You may not be aware of any history of addiction in your family. You may even live a good portion of your life without developing an addiction. Maybe you didn’t try cigarettes as a teenager, and maybe you don’t use alcohol.
Then, you have hip replacement surgery when you are sixty. This is the first time you are exposed to opioids, but these pain relievers are necessary for your post-surgery recovery. Without a family history of addiction, the doctor has no reason for concern when he prescribes you pain-relievers. Six months after surgery, you are still taking the pills and cannot stop.
How Do Genetics Affect Addiction?
While genetics do play a role in addiction, they are not the deciding factor. Regardless of your specific genetic makeup, you can develop an addiction. If you are genetically pre-disposed to developing addiction, you can avoid it. Genetics is just one part of the addiction equation.
There are several components to addiction besides genetics, including:
- Access to substances
- Environment
- Mental health
- Physical health
- History of trauma
- Family history of addiction
Genetics affect drug consumption for some people, making addiction nearly impossible. If you are predisposed to avoid drugs because of your genetic makeup, you probably don’t have to worry about addiction. The best way to avoid addiction, of course, is to abstain from drug use in the first place. For most people, however, complete abstinence from the beginning is not likely.
Genetics can affect how you experience drugs and alcohol. For most people, there is a pleasurable feeling associated with taking drugs, which is why they continue. Even if the drugs are prescribed for legitimate medical reasons, when they alleviate the painful symptoms associated with the medical condition, there is a feeling of pleasure.
Some people, however, are genetically programmed not to experience that same pleasurable response to drugs. For some, it’s the feeling of being out of control that they cannot tolerate. Their need to maintain control over themselves and their environment — a characteristic that is at least partially genetically based — causes them to avoid substances that cause any dissociative sensations.
For some people, consuming alcohol initiates a blotchy red coloration of the face that is unpleasant and embarrassing. Alcohol flush reaction is not an indication of inebriation, but rather evidence of a genetic condition that affects the natural production of enzymes required to metabolize alcohol. People who have this genetic condition are less likely to consume alcohol and, therefore, their rates of alcoholism are low. Alcohol flush reaction is often associated with Asian ancestry. Approximately 36% of people of Japanese, Chinese, or Korean decent exhibit flushing, nausea and racing heart rate with exposure to any amount of alcohol.
There are a number of different genetic variations that make it difficult or impossible for some people to derive pleasure from drugs. Some of these variations, like the enzyme production to metabolize alcohol, only affect certain drugs. Other variations, like the intolerance of feeling out of control, affect the whole pleasure cycle in general and are not specific to one drug or another.
What Can Genes Tell Us About Addiction?
There are several implications to genetic research into addiction. The ultimate goal would be to discover a connection that could be predicted and ultimately used to treat addiction. That day is a long way off, still, but many good interim benefits are coming out of continuing genetic research.
A recent study of the genetics of marijuana addiction identified the specific genes associated with marijuana addiction. Marijuana users develop addiction at a rate of about 10%, which is one of the reasons marijuana is popularly assumed to be non-addictive.
By isolating the genes for marijuana addiction, though, scientists have made another interesting discovery in the field of mental health. The same genes that are associated with marijuana addiction are also associated with depression and schizophrenia. This discovery explains the connection between marijuana addiction and depression, which was earlier believed to be causal.
One of the genes identified in this study is also responsible for calcium levels. With more research, this could someday provide a physical warning factor for marijuana addiction, depression and schizophrenia. It may be impossible to see your genes, especially the ones that are not expressive, but connecting a physical condition with an invisible genetic factor might make it easier to know what you’re dealing with.
The same genes are also associated with attention deficit disorder (ADD) which, in turn, is connected to marijuana use. While it is too early to use this genetic information to make predictions, being able to isolate certain genes and group them together with disorders is a start. Knowing that ADD, depression and marijuana addiction are all associated through certain genes increases our understanding of how these factors may interact.
How Do Genetics Separate Addicts From Non-Addicts?
The biggest genetic difference that has been isolated so far between addicts and non-addicts is their ability to recover. Addiction is possible no matter what your genetic profile might be. Genetics are not the deciding factor in whether you become and addict or not.
It is still impossible to determine in advance whether someone is addiction-prone or not. There are observable family traits, but these do not necessarily indicate the presence of the genes associated with addiction. Genes can be carried but not expressed, just like the green-eyed child of two blue-eyed parents.
Although some genes have been identified as being associated with addiction, these findings are not complete. There are so many gene combinations possible, and so many that can be associated with addiction, that much more testing is needed. Genetic pre-disposition to addiction is not as simple as identifying the addiction gene and testing for it.
After an addiction is diagnosed, however, it’s easier to identify a genetic pre-disposition. Even this identification is primarily based on observable evidence and not on genetic testing. Based on a person’s reaction to a drug experience, and some observations about that person’s family history and personal history with substance abuse, a reasonable inference can be made for the presence of a genetic pre-disposition to addiction.
Since someone who is genetically pre-disposed to addiction generally accelerates through the development of addiction faster than others, it follows that overcoming addiction would be harder. It is similar to dropping a sponge into a bucket of water. If you pull the sponge back out before it becomes submerged, there is less water to wring out of it. If you wait for the sponge to become fully submerged, wringing the water out will be a bigger job because the sponge is fully saturated.
Addiction is a force that takes control of all aspects of your life and becomes stronger over time. The amount of time it takes for addiction to fully develop, though, is based on several variables. Someone who is genetically pre-disposed to addiction will develop an addiction faster and more completely than others will. This distinction has ramifications on the length and intensity of rehabilitation required to recover.
How to Determine Genetic Pre-disposition to Addiction
Recent studies give us more insight to the genetics of addiction. A study of the drug use habits of twins revealed and confirmed the genetic connections of drug abuse. Identical twins share the same genetic makeup, while fraternal twins are closer genetically than non-twin siblings, but are not identical.
One twin study sponsored by the National Institute on Drug Abuse supported previous findings that genetics were not the only or most influential factor in beginning drug use. Environmental factors, such as family and social interactions, are also part of a person’s decision to try recreational drug use. Genetics, however, were a major factor in the progression from use to abuse and addiction.
The implication of these research conclusions is that before the drug use takes place is the most effective time to counteract the genetic predisposition for addiction. If that predisposition can be recognized early, it can be overridden with environmental factors, including education and social pressures away from drug use.
With respect specifically to cocaine and marijuana use, the study found that the use, abuse and dependence rates among different types of twins varied. Identical twins were most likely to behave the same way: When one used drugs, 54% of the twins used drugs also. These rates dropped for abuse and addiction. There was a 35% likelihood that both identical twins would face addiction, while among fraternal twins, there was a 0% instance of both twins becoming addicted.
Researchers concluded that, while drug use does not necessarily rely on genetics, abuse and addiction were highly dependent on genetic disposition. Genetics may not make you a drug user, but if you become a drug user, genetics could cause you to progress to abuse and addiction. Of course, the detail missing from this conclusion is how to determine if you are genetically pre-disposed to addiction in the first place.
Another twin study determined that genetics influence addiction to different substances at different rates. The rate of influence of genetics on heroin addiction is stronger than that for other drugs. This study also supported the finding that abuse and addiction are more highly influenced by genetics than drug use.
There is also a disparity in the rate of addiction between men and women. About 47% of the difference between female twins’ addiction rate can be attributed to genetics. The same measure among male twins is 79%. In addiction, men are more heavily influenced by genetic factors than women.
Such a difference in genetic influence by gender has implications for recovery programs. It is clear that if men and women do not come to addiction by the same influences, then they would not be best served by the same recovery programs. We could further speculate that if genetics are responsible for more of a man’s addiction experience, then women have a predominance of other causes they need to explore in recovery.
Getting the Best Treatment
Continued genetic research into the connections to addiction support the argument for individualized addiction treatment programs. People get to addiction in very different ways. Your path to addiction is personal and based on genetics, physical health, mental health, environment and several other factors. While there are similarities in addiction scenarios, there are a lot of differences, as well.
Genetic research is beginning to uncover a multitude of variables just within this one part of the addiction equation. Of all the possible genetic variations between two parents, even siblings can display very different genetic traits. When we consider all the different genes involved in addiction, that just widens the field of possible genetic combinations that could represent addiction.
On top of all that, there are variables for different substances. Someone of Asian descent who is genetically programmed to under-produce the enzyme necessary to metabolize alcohol may have no trouble experiencing the high of cocaine. Some genes have been identified as being specific to marijuana addiction, but they do not necessarily affect addiction to other substances.
An addiction diagnosis is only the beginning of understanding what’s going on in a person’s brain. To produce a lasting recovery from that addiction, much more individual study is required. Each of the contributing components to that specific addiction then need to be addressed in a comprehensive recovery program. Genetics can help unlock the mysteries of addiction, but there is a lot more to learn before geneticists hold the key to recovery.
In the meantime, here at 12 Keys, we continue to provide individualized treatment programs designed to meet the needs of each of our clients. We assess our clients to figure out where they are, and we meet them there with the right treatment at the right time. Our comprehensive program addresses every aspect of addiction, including any underlying mental health issues that may have precipitated the addiction or developed subsequently.
At 12 Keys, we use a combination of science, spirit, body and family to overcome addiction and help clients create a lasting recovery. Whether addiction is genetically triggered or the result of the convergence of other factors in your life, you need an effective recovery program. Everyone deserves to live a healthy, happy life, and at 12 Keys, we guide our clients down that path.
If you or someone you love is struggling with addiction because of a genetic predisposition or any other reason, contact 12 Keys today. Let us use the latest science-based recovery modalities, along with our compassion and experience in addiction recovery, to help you start healing today.
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