2 gene mutations may raise eating disorder risk

US researchers said Tuesday they have found two gene mutations associated with increased risk of developing eating disorders. By studying the genetics of two families severely affected by eating disorders, researchers from the University of Iowa and University of Texas Southwestern Medical Center identified mutations in two genes which interact in the same signaling pathway in the brain. The findings suggest that this pathway might represent a new target for understanding and potentially treating eating disorders such as anorexia nervosa and bulimia, the researchers said. Anorexia nervosa and bulimia nervosa are fairly common, especially among women. They affect between 1 and 3 percent of women. They also are among the most lethal of all psychiatric diseases; about 1 in 1,000 women will die from anorexia. In the study, the researchers analyzed 20 members from three generations of one family, including 10 affected individuals and 10 unaffected by eating disorders, and eight members of a second family, including six affected and two unaffected. In the larger family, they discovered a mutation in a gene called estrogen-related receptor alpha (ESRRA). In the second family, they found a mutation in a gene known as histone deacetylase 4 (HDAC4). Both mutations decreased the activity of ESRRA protein, thus increasing the risk of eating disorders, the researchers said. The researchers said they plan to study the role of these genes in mice and in cultured neurons to find out exactly what they are doing in the brain. They will also look for ways to modify the genes\' activity, with the long-term goal of finding small molecules that might be developed into therapies for eating disorders.