Anorexia nervosa is among the most challenging mental disorders for rehab facilities to treat successfully. Many individuals who suffer from the condition simply relapse after completing treatment. Now, a new study has found that genetics may be at the heart of this grim reality.

A team of researchers from The Children's Hospital of Philadelphia analyzed genetic data from more than 1,000 participants with anorexia. The information was compared to data from individuals who did not have the condition.

The researchers found that individuals who suffered from anorexia had certain genetic variants in common. The findings confirm smaller studies conducted previously among twins, which showed common genetic markers among individuals with the disorder.

While anorexia is relatively rare, it affects a disproportionate number of women. In addition to explaining the association among families, the results of the study could clear up the reasons behind these gender differences.

Researchers said that the findings could help them determine through hereditary associations individuals who are at the greatest risk of developing anorexia. This could make it easier for these individuals to seek treatment from rehab facilities in the earliest stages of the condition, while it is most treatable.