Scientists have discovered genetic clues to the cause of restless leg syndrome, a condition common among older adults. The discovery could help identify those individuals at greatest risk of the condition and point to potential ways to treat it. Restless leg syndrome can cause an unpleasant crawling sensation in the legs and an overwhelming urge to move them.
Some people experience the symptoms only occasionally, while others get symptoms every day. Symptoms are usually worse in the evening or at night-time and can severely impair sleep. Despite the condition being relatively common – up to one in 10 older adults experience symptoms, while 2-3% are severely affected and seek medical help – little is known about its causes.
People with restless leg syndrome often have other conditions, such as depression or anxiety, cardiovascular disorders, hypertension, and diabetes, but the reason why is not known. Previous studies had identified 22 genetic risk loci – that is, regions of our genome that contain changes associated with increased risk of developing the condition. But there are still no known 'biomarkers' – such as genetic signatures – that could be used to objectively diagnose the condition.
To explore the condition further, an international team led by researchers at the Helmholtz Munich Institute of Neurogenomics, Institute of Human Genetics of the Technical University of Munich (TUM) and the University of Cambridge pooled and analysed data from three genome-wide.