U.S. researchers aim to map genetics of eating disorders

Study will identify those at high risk, develop improved treatments

CHAPEL HILL, N.C.— A new initiative at the University of North Carolina-Chapel Hill is kicking off a genetic study of eating disorders that it says will be the largest of its kind.

If successful, the study, conducted by the Eating Disorders Genetic Initiative, will be able to identify hundreds of genes that influence a person’s likelihood of suffering from three prominent disorders: anorexia nervosa, bulimia nervosa and binge-eating disorder.

That knowledge could significantly improve the way those illnesses are treated, said Cynthia Bulik, a professor at the UNC School of Medicine and head of EDGI.

“It might help us with prediction and prevention in the future,” Bulik said in a phone interview. “That is a direction we hope to go in: help us identify those who are high risk.”

Eating disorders affect a large number of people. About nine per cent of Americans, or 28.8 million, will have an eating disorder in their lifetime, according to the National Association of Anorexia Nervosa and Associated Disorders. And that number could be increasing, as the coronaviru s pandemic pushes the country into a mental health crisis as well. Bulik recently co-authored a study of individuals with eating disorders in the U.S. and the Netherlands that reported an increase in anxiety during the pandemic, which has disrupted the lives and routines of millions.

“We are clearly in the midst of a mental health pandemic,” Bulik said. “The things (participants) talked about most was the lack of structure in their days … (and) a lack of social support. Eating disorders thrive in isolation.”

While there have been numerous psychiatric studies of eating disorders, the biologic underpinnings of the illness are still relatively unknown and there are no medications to treat eating disorders. “Part of that is because we haven’t understood the biology of eating disorders,” she said.

EDGI is seeking 100,000 people across the world with a history of an eating disorder to volunteer as part of the genetic study. In the U.S., it is looking to reach 6,000 participants. In addition to genetics, EDGI will also survey participants from around the world to see how environmental factors influence the disorders. Bulik said it will be important for EDGI to get a very diverse sample of volunteers. She hopes to complete the collection portion of the study by 2022.

The study will build off a previous one that focused specifically on anorexia nervosa. Bulik said that study had transformational findings, identifying eight areas of the genome with significant associations with anorexia nervosa.

Finding evidence for those associations, she said, helps reduce misunderstandings around the illness.

“These are serious illnesses with genetic bases and we need to bust those myths about them being a choice,” Bulik said. “One of the things that this research does is bust those myths. We can say with complete confidence that genes are involved.”

That previous research only studied 17,000 participants and

Bulik said the data would be much more reliable with a larger pool of volunteers. By expanding the research to include other eating disorders, EDGI could determine if certain genetics predispose someone to multiple illnesses or whether they all have unique causes.

“My gut says and preliminary information shows that there might be some shared genetic factors across all three disorders, but also unique genetic factors associated with them that decides the path (of treatment) you go down,” she said. “There is not a clear demarcation between these disorders. People will toggle back and forth between anorexia and bulimia. They are not mutually exclusive.”

EDGI is looking for participants who are 18 years or over and have, at any point in their lives, experienced anorexia nervosa, bulimia nervosa or bingeeating disorder. Visit edgi.org to volunteer or learn more.

“It might help us with prediction and prevention in the future.” CYNTHIA BULIK PROFESSOR AT THE UNC SCHOOL OF MEDICINE AND HEAD OF EDGI