The origins of the eating disorder anorexia nervosa have genetic as well as psychiatric causes, according to a new international study, published in Nature Genetics.
Researchers looked at 16,992 people with anorexia and 55,525 people without the disease, from 17 countries. Their DNA was analysed to find mutations in genetic instructions that were more common in anorexia patients.
The study found some mutations also presented in other psychiatric disorders such obsessive-compulsive disorder, anxiety, and schizophrenia. However, they also found mutations in the instructions that control the body's metabolism, particularly those involving blood sugar levels and body fat.
‘What our study means is we can no longer treat anorexia, and perhaps other eating disorders, as purely psychiatric or psychological,’ said Gerome Breen, a geneticist at King’s College London who co-led the study.
‘Anorexia has the expected correlations with anxiety, depression and OCD, but it also has this set of apparently healthy metabolic correlations that we don’t see in any other psychiatric disorder.
According to the charity Beat, approximately 1.25 million people in the UK have an eating disorder, with anorexia accounting for approximately 8% of those.
‘This is groundbreaking research that significantly increases our understanding of the genetic origins of this serious illness,’ said Andrew Radford, the chief executive of Beat.
‘We strongly encourage researchers to examine the results of this study and consider how it can contribute to the development of new treatments so we can end the pain and suffering of eating disorders.’