Genetic Study of Anorexia Nervosa Fueled by NIMH Grant

It’s an exciting first for the field of eating disorders: a sizable federal grant to advance the study of the genetics of anorexia nervosa. In September, The National Institute of Mental Health (NIMH) awarded a $10 million grant to continue work to unravel the genetics of anorexia nervosa. This is the largest single financial commitment the NIMH has made to the field of eating disorders, and the first-ever government-funded genetic study of anorexia nervosa.

The study brings together 10 groups of researchers from North America and Europe at 7 centers in the U.S. and 3 in Canada, Germany, and Great Britain. One year of funding is also provided for analysis of the data and manuscript preparation. (See the box for participating groups). The study will be directed by Walter H. Kaye, MD, University of Pittsburgh and Wade Barrettini, MD, PhD, at the University of Pennsylvania.

During the five-year study, researchers will seek to find regions of the human genome that contain genes that affect the risk for anorexia nervosa. To do so, researchers will recruit families with two or more members, mostly siblings, who have or had anorexia nervosa, and will analyze their DNA.

Toward an International Database

According to Craig Johnson, PhD, of Laureate Psychiatric Clinic and Hospital, Tulsa, OK, a study investigator, the outcome will help build an international genetics database for anorexia nervosa. Currently there is no DNA databank for anorexia nervosa or bulimia nervosa, he said. Dr. Johnson added that any researcher in the world who is qualified to do genetic research could apply to NIMH and gain access to the DNA database. The database will create a tremendous opportunity to further our understanding of anorexia nervosa and bulimia nervosa, he said.

Building Upon the Success of a Prior Study

The new study will build upon the 5 years of genetic research by the Collaborative Study of the Genetics of Anorexia Nervosa and Bulimia Nervosa. This study was also headed by Dr. Kaye, and funded by a private group, the Price Foundation. Many of the centers participating in the first study will continue their work in the new NIMH-funded study.

The results of the previous genetic study laid the groundwork for the new study, according to Dr. Johnson. First, the results from the preliminary study were very promising. Second, The Collaborative Group had a multi-year track record of being able to cooperate—and had a remarkable record in which all 10 international sites worked well together. Finally, he noted, families affected by anorexia nervosa have been extremely willing to participate in the research and study of the disease.

Researchers will begin recruiting families soon. The goal is to find 400 families with two or more members who have had or currently have anorexia nervosa. Study participation will be relatively easy: interested families will first have a telephone interview, and those who qualify can then have blood drawn by their local laboratories for DNA studies. Participants will receive a small honorarium for their participation.

How will the researchers find the families? A variety of different recruitment strategies will be used, beginning with advertisements from current treatment centers. Families from any part of the U.S., with at least 2 members who have had a diagnosis or symptoms of anorexia nervosa and who are willing to participate are candidates. Dr. Johnson noted that finding the study participants will be challenging, since the inclusion criteria are rigid and a sizeable number of participants—400 families—are needed. It will require an extraordinary recruitment effort, he said. Several versions of genetic sampling have already been done, so that it is possible to progressively close in on the extent and nature of the genetic contribution to anorexia nervosa.

Answering Difficult Questions

As Dr. Johnson noted, the main question that has been difficult to answer thus far from the sociocultural-psychological family perspective is if 100 14-year-old girls are all dieting, exercising, reducing calories and fats, or struggling with body image dissatisfaction, why do only 3 develop a more severe form of anorexia nervosa or bulimia nervosa? Family studies have revealed that relatives of persons with eating disorders have a substantially greater risk of developing eating disorders themselves. Preliminary studies indicate that individuals with a mother or sister who has had anorexia nervosa are 12 times more likely than people without any family history of the disorder to develop anorexia nervosa. These same family members have a fourfold greater risk for developing bulimia nervosa. A number of traits such as perfectionism, anxiety and obessionality contribute to a risk for developing anorexia nervosa.

Dr. Johnson said, “The hope for the future would be that eventually there would be some ability to definitely diagnose and more importantly to intervene as a result of understanding the genetics and neurochemistry and biology of the illness.”

In addition to developing new and more effective diagnosis and treatment for anorexia nervosa, studies that identify the genetic basis for illnesses such as anorexia nervosa will help reduce the unfair stigma aimed at mentally ill persons. Dr. Johnson noted, “Part of the great thing about doing the research is that hopefully we will be able to reduce some of the shame associated with these disorders by showing that these individuals probably had some genetic predisposition that made them more vulnerable to the disorder.”

Research Centers Participating in the Genetic Study

Walter H. Kaye, MD (co-principal investigator) and Maria LaVia, MD
University of Pittsburgh

Wade Berrettini, MD, PHD (co-principal investigator)
University of Pennsylvania School of Medicine, Philadelphia

Katherine A. Halmi, MD
Cornell University, White Plains, NY

Michael Strober, PhD
University of California, Los Angeles

James E. Mitchell, MD
University of North Dakota, Fargo

Craig L. Johnson, PhD
Laureate Clinic and Hospital, Tulsa, OK

Harry A. Brandt, MD and Steven Crawford, MD
St. Joseph Medical Center, Towson, MD

Manfred M. Fichter, MD
Roseneck Hospital (affiliated with the University of Munich, Prien, Chiemsee, Germany)

Allan S. Kaplan, MD, FRCP and D. Blake Woodside, MD, FRCP
University Health Network of Toronto General Hospital, Toronto, Canada

Ian Jones, MD, Nick Craddock, MD, and David Robertson, MD
University of Birmingham, England

Data will be analyzed by Drs. Bernie Devlin and Walter Kaye and Laura Thornton, University of Pittsburgh; and Dr. Cindy Bulik, Virginia Commonwealth University, and Dr. Kelly Klump, Michigan State University. Dr. Lisa Lilenfeld at Georgia State University will manage the genetic and psychiatric data.

For more information, check the study website, www.angenetics.org, or call the toll-free information number, 1-888-895-3886. E-mail: edresearch@msx.upmc.edu.