Study finds distinct DNA signals in binge eating, anorexia

A team in London has put nearly 40,000 people with binge-eating behaviour and more than 1.2 million unaffected people into the same genetic comparison. Led by the Institute of Psychiatry, Psychology & Neuroscience at King’s College London, the researchers found six regions of DNA associated with binge eating and eight associated with anorexia nervosa.

The study, published in Nature Mental Health, also included about 25,000 people with anorexia nervosa. Six of the anorexia-linked regions had already been implicated in a 2019 genetic study, while two were identified for the first time here. The research examined binge eating as a symptom, rather than focusing only on a specific diagnosis such as binge-eating disorder.

The central finding is a separation that body mass index alone cannot provide. Although body weight is relevant to both conditions, the genetic associations for binge eating and anorexia nervosa were not the same as those associated with BMI. Some binge-eating regions had previously been linked to body-size traits, including one near FTO, suggesting that binge eating may account for part of the connection between FTO and higher BMI.

The practical change is in the direction of research, not an immediate clinical test: genetic studies can now look beyond weight to biology shared or unique across eating-disorder symptoms. Dr. Jonathan Coleman of King’s IoPPN said the work moves beyond anorexia nervosa toward understanding binge eating, with the researchers hoping future studies will improve lives for people with all eating disorders.

The limits are visible in the design. The analysis found associations, not a standalone explanation for why an individual develops an eating disorder, and the reported loci were identified in people from European backgrounds. The team’s next plans include other conditions, such as atypical presentations and avoidant/restrictive food intake disorder, alongside analyses of global ancestries.