Research on Anorexia and Genetics

Contributor: W. Travis Stewart, Licensed Professional Counselor, Revision Recovery Coaching

mastomys-491576_640Esrra-null female mice display a reduced operant response to a high-fat diet, compulsivity/behavioral rigidity, and social deficits. Selective Esrra knockdown in the prefrontal and orbitofrontal cortices of adult female mice recapitulates reduced operant response and increased compulsivity, respectively.

These results indicate that Esrra deficiency in the mouse brain impairs behavioral responses in multiple functional domains.

Got that? Yeah, me neither.

Making Genetic Studies on Anorexia More Accessible

The paragraph above is quoted from a recent research paper on the role of genetics and the brain in the development of anorexia nervosa. I think I lost a few brain cells just reading it; and I have TWO master’s degrees and passed a class called Research Methods in graduate school. If this is confusing for me, a professional working in the field of eating disorders, then I would guess that many Eating Disorder Hope readers feel the same way.

My goal for this article is to make research on genetics, anorexia and eating disorders in general more accessible to the average reader.

So, if you would like a primer on understanding research, genetics and anorexia, read on. If you understood that first paragraph, I encourage you to move along—there is nothing for you to see here.

Definitions

dictionary-698538_640Let’s start with defining some key words.

According to Merriam-Webster dictionary Genetics is “the makeup and phenomena of an organism, type, group, or condition”. OK. This isn’t getting any easier. Let’s look at the definition for kids: “the scientific study of how the characteristics of living things are controlled by genes”. That’s better. It’s amazing how difficult we adults can make things. Genetics is the study of genes. What is a gene? A gene is a unit of DNA which controls traits in all living things.

So what is DNA? The Merriam-Webster definition for kids says, “a large organic molecule that carries genetic information in the chromosomes and resembles a twisted ladder”. You don’t even want to see the adult version.

Heritability

Heritability is another word you will commonly find in genetic studies. According to the website scienceofeds.org “Heritability measure the amount of the variability in an observable trait/behavior that can be attributed to genetic variation.” In other words, heritability tries to measure how big of a role genetics plays in whatever is being measured (such as height, eye-color, anorexia, etc.)

Twin studies appear to be the best way to measure how much a behavior is affected by genetics vs environment in the development of behaviors. There are two types of twin studies. One type of twin study looks at the lives of twins who were raised together in the same home.

In this type of study, one or both twins may have an eating disorder. The other type of twin study—which is the most helpful—is to study twins separated at birth and raised in different environments. The idea is that if both twins develop an eating disorder while being raised in completely different environments then there would appear to be a strong genetic component in the development of the behavior.

Risk vs Cause

microscope-275984_1280What causes anorexia? This is an important question because if the cause of the problem can be clearly stated then prevention and treatment action steps will be more accurately developed. For example – if we can determine that cultural factors are the cause of anorexia—such as thin celebrities and photoshopped images—then we can focus our efforts at changing those things. On the other hand, if a particular gene is identified as the cause then, as science moves forward, we might be able to develop gene therapy to treat and prevent eating disorders.

Unfortunately, it’s not so simple. Eating disorders appear to be incredibly complex and result from that combination of nature and nurture. So, instead of cause, researchers look at things like risk. Risk can be measured pretty accurately using family history and genetics. We can take a history and determine how many of your ancestors struggled with anorexia, anxiety or related issues. If we look at enough families we can begin to connect the dots and find out who is more at risk for anorexia.

Nature vs. Nurture

This question is interested in whether behavior is determined either by genetics or environment. Do genetics or experiences determine our behavior? The answer seems to be a very clear “Yes.” Who we are as humans is a result of complex and immeasurable combinations of genetic information influenced by our culture, our environment families, our experiences and our choices.

Let’s hear how a couple of experts in the field address the question of nature vs. nurture; science writer Carrie Arnold, writes in her book Decoding Anorexia:

beach-434233Researchers haven’t found a single gene that causes anorexia, and it’s unlikely they will. Most illnesses aren’t caused by a malfunction in a single gene. Rather, genes generally increase or decrease your risk of developing the disease. This risk is subsequently influenced by the environment in which a person lives. Anorexia arises from a complex interaction between malfunctioning hunger signals, anxiety, depression, and difficulties in decision making1.

Genes and Environment

And Dr. Cynthia Bulik, at the University of North Carolina stated in a Twitter chat with Eating Disorder Hope2, “Genes load the gun, but environment pulls the trigger.”

So What? Who knows what science will bring us in the future when it comes to understanding and treating anorexia. In the meantime we need to ask the tough question or, “so what?” What if we figure out it is primarily genetic or that the source of the problem is a brain that can’t process hunger cues accurately?

You Are Responsible for Your Recovery

eye-413734_640At some point that may mean a medication that repairs the brain. But, what does it mean for those struggling now? It means you are responsible for your recovery. To live free of anorexia requires the hard work of understanding the contributing factors and learning to respond in healthy ways.

Maybe a contributing factor for you is how a loved one about their own weight. If so, you need to learn how to set boundaries with your loved one and respond to the emotional triggers. Maybe a contributing factor is seeing a skinny model in a magazine.

If so, you need to change your reading habits and learn to listen to the thoughts and anxieties connected to those images in a different manor. Maybe a contributing factor is the way your brain does or does not respond to hunger. Then you need to learn to recognize what your brain is doing and begin to learn techniques on how to retrain your brain.

Regardless of the cause and source of anorexia in your life, it’s up to you to take the steps to learn all that you can, ask for help and make courageous choices.


References:

  1. Arnold, Carrie, Decoding Anorexia; How Breakthroughs in Science Offer Hope for Eating Disorders, p. 11.
  2. https://www.eatingdisorderhope.com/wp-content/uploads/2015/05/Anorexia-Genetics-ANGI-Tweet-Chat-Transcript.pdf

About the Author:

Travis Stewart photoTravis Stewart is a Licensed Professional Counselor who has worked in the field of eating disorders since 2003. He also offers recovery coaching for individuals wanting to develop more autonomy, mastery and purpose in their lives.

Last Updated & Reviewed By: Jacquelyn Ekern, MS, LPC on July 31st, 2015
Published on EatingDisorderHope.com