A distorted body image, an extreme fear of putting on pounds, abnormally low body weight — all hallmarks of the eating disorder anorexia nervosa. Long thought to be a psychiatric condition, a new study reveals it also might have genetic underpinnings. Analyzing the DNA of about 3,500 diagnosed people and nearly 11,000 without the disorder, researchers homed in on a genetic locus — a gene’s location on a chromosome — that’s involved in the body’s metabolic processes and seems to be associated with the disorder. Scientists are now closer to a more complete picture of this potentially deadly condition.