Eating disorder sufferers could have a genetic mutation which makes them more susceptible to the condition, scientists have found.
Two gene mutations have been identified that are associated with an increased risk of developing conditions such as anorexia nervosa and bulimia.
By studying the genetics of two families severely affected by eating disorders, scientists from the University of Iowa and University of Texas Southwestern Medical Center identified mutations in two genes which interact in the same signalling pathway in the brain.
The researchers said that this pathway might represent a new target for understanding and potentially treating eating disorders.
The study, published in the Journal of Clinical Investigation, suggests that people who have mutations that reduce the activity of a protein called estrogen-related receptor alpha (ESRRA), have an increased risk of developing the disorders.
The scientists examined 20 members from three generations of one family - including 10 people who were affected by eating disorders - and eight members of a second family, six of whom suffered from the condition.
In one family they identified a mutation in the gene encoding of ESRRA in the family members who suffered from eating disorders.
In the other family they found a mutation in the gene encoding of the protein histone deacetylase 4 (HDAC4).
The mutant forms of both ERRSA and HDAC4 resulted in reduced expression of known ERRSA-dependent genes.
These findings indicate that individuals with mutations that reduce ESRRA activity have an increased risk of developing eating disorders, the researchers concluded.
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