Familiality and heritability of binge eating disorder: results of a case-control family study and a twin study.

OBJECTIVE To estimate the familiality and heritability of binge eating disorder (BED). METHOD We used a new ACE structural equation model to estimate heritability from a case-control family study of BED conducted in the Boston area. The sample consisted of 150 overweight/obese probands with lifetime BED by DSM-IV criteria, 150 overweight/obese probands without lifetime BED, and 888 of their first-degree relatives. We compared our findings with those from a study of binge eating (in the absence of compensatory behaviors) among 7,831 Norwegian twins. RESULTS The prevalence of BED differed by sex and by age. In the case-control family study, BED was found to aggregate in families, and heritability was estimated as 57% (CI: 30-77%). Including shared environment did not substantially improve the model's fit, nor did allowing sex-specific heritability. Findings from the twin study were similar. CONCLUSION BED appears to aggregate in families and have a significant genetic component.