Eating Disorders and Genetics: The Newfound Link
A groundbreaking new study finds compelling evidence
A new global study led by researchers from the University of North Carolina, published Monday in the journal Nature Genetics, offers the strongest evidence to date that anorexia nervosa not only has a genetic component, but that it is also associated with unique metabolic characteristics that make it more difficult for people with the disorder to gain and maintain weight, even after recovery.
Mainstream narratives about eating disorders like anorexia nervosa tend to focus on the psychological and social risk factors for the disease, and as a result, anorexia is generally viewed as a learned behavior or a response to environmental pressures. But often the disease can run in families. Experts have wondered if some people have a higher familial risk for the disorder, as someone might have a greater risk for breast cancer or Alzheimer’s disease.
Until now, research in the field of psychiatric genetics hadn’t found much evidence for a genetic basis for anorexia nervosa, in part because sample sizes were too small to conclude anything of significance. Anorexia nervosa affects an estimated 0.6% of the population in the U.S., making it difficult to gather enough DNA for statistical analysis that’s powerful enough to find subtle differences across thousands of genes. However, the disorder has one of the highest mortality rates of any psychiatric illness at around 6%, second only to substance use disorders for opioids, amphetamines, and cocaine with a 15% mortality rate, lending urgency to the research.
In the UNC study, researchers identified eight genetic markers in anorexia nervosa patients that may have contributed to their risk for developing the disease. Some of these genes were also linked to other psychiatric disorders like depression and obsessive compulsive disorder, which hints at a genetic factor for the reason that some people with the eating disorder also present with these additional illnesses as well.
But perhaps the most intriguing aspect of these genetic markers is that some of these genes are also associated with a low body mass index.
“This panel of genetic correlations suggests that we really need to be looking at two…