Relief may be at hand, thanks to German researchers, for millions of people kept awake by twitching legs. Teams at the Max Plank Institute of Psychiatry and Munich's Technical University and National Research Centre for Environment and Health have found genetic variations that can cause nocturnal restless legs. Restless leg syndrome can disturb sleep and the prevalence of the disorder increases with age. The discovery from the study of more than 2,000 people could lead to new treatments for the condition, the researchers said.