Genes Found to be Associated with Eating Disorders

           In a recent article on USNews.com about a study published in the Journal of Clinical Investigation, two genes have been discovered to increase the risk of developing two prominent eating disorders.  These two eating disorders are anorexia nervosa and bulimia.  The study revealed that mutations to two different genes known as ESRRA and HDAC4 cause people to have an increased risk of developing these eating disorders.  More specifically, a mutation in the ESRRA gene leads to a 90% chance of developing anorexia nervosa or bulimia and a mutation in the HDAC4 gene increases the risk to 85%.  The researchers from the University of Iowa and the University of Texas Southwestern Medical Center came to this conclusion by studying individual families where eating disorders have been frequent through generations.  Both the ESRRA and HDAC4 genes were found to interact within the same signaling pathway in the brain.  According to Michael Lutter, the senior author of the study, a very general view of how these mutations in both genes work is that the mutations disrupt the signaling pathway of these genes in the brain and therefore, “blocks a person’s ability to want to eat.  Normally, how the signaling pathway of both these genes functions is that when the body has an increased need for calories, the pathway in the brain interacts with these two genes to increase a person’s desire for food”.  The mutations of the ESRRA and HDAC4 are quite rare.  In fact, it has been calculated that 1 in 1,000 people have the ESRRA mutation and 2 in 10,000 people have the HDAC4 mutation.  Subjects that were very young had one of the gene mutations, but didn’t display any signs of an eating disorder.  Lutter explains this by stating that those young subjects just haven’t developed the eating disorder yet.

            As a result of this study, it has now been proven that eating disorders are not solely caused by environmental factors.  Genetic factors definitely play a role in whether or not a person develops anorexia nervosa and bulimia.  Leslie Sim who is a clinical child psychologist at the Mayo Clinic says now with this recent findings, parents no longer have to blame themselves for causing their child’s eating disorder.  However, Lutter and Sims says that genetic and environmental factors both play a role in the development of an eating disorder.  More specifically, Lutter says that “between 50-70 percent of the risk of developing an eating disorder is genetic, and 30 percent to 50 percent of the risk is considered environmental.” 

Men and especially women are reminded everyday through the media that the perfect body image is someone who is thin, muscular, and beautiful.  Unfortunately, people feel that they need to look like all the stars and celebrities.  As a result, people put a lot of pressure on themselves to be thin, muscular, and beautiful.  Therefore, both “anorexia nervosa and bulimia nervosa affect between 1 percent and 3 percent of women” according to the study.  Comparing men to women, more women develop eating disorders than men.  In my abnormal psychology class, I learned about anorexia nervosa and bulimia.  Anorexia nervosa is defined in the DSM-IV, which is the Diagnostic and Statistical Manual of Mental Disorders, as not maintaining normal body weight by not eating, fearing to gain weight, and having an inaccurate perception of body size.  On the other hand, bulimia is when people can’t control their eating habits and eat large amounts of food.  After, the person usually purges to compensate for eating so much or they might fast or exercise a lot.  Bulimia nervosa is actually more common than anorexia nervosa.  I thought that this news article was very interesting.  It now gives people a definite answer as to what causes the eating disorders of anorexia nervosa and bulimia.  I agree with Lutter and Sim that these eating disorders are caused by both genetic and environmental factors.  It is unfortunate that people feel pressured from the media to be thin, muscular, and beautiful.  People should love themselves just the way they are and not worry about looking like famous celebrities.  People will be much happier if they were comfortable with their body image.