Researchers at the University of Edinburgh have discovered differences in the DNA of people suffering from chronic fatigue syndrome, which helps dispel the notion that this condition is psychological or due to laziness. Their study found eight regions of the genetic code that differ in people with myalgic encephalomyelitis, known as chronic fatigue syndrome, compared to healthy volunteers. The researchers stated that this discovery provides the first evidence that genes contribute to the likelihood of developing the disease. Key features of the condition include worsening fatigue and pain, and brain fog after simple physical or mental activity. It is believed that this condition affects about 67 million people worldwide. The study analyzed DNA samples from 15,579 individuals who reported having the syndrome in a survey, and 259,909 people without the condition, all of European descent.

The researchers identified at least two gene regions related to how the body responds to infection, consistent with reports that symptoms often begin after an infectious illness. Previously, researchers identified another gene region in people with chronic pain, another common symptom of the condition.