They found that one group of flies, with a mutation in the gene they would later call Wide Awake (or Wake for short), had trouble falling asleep at night, a malady that looked a lot like sleep - onset insomnia in humans.
«Among normal adults, sleep difficulties and insomnia have predicted onsetof alcohol use one year later, and increased risk of any illicit drug use disorder and nicotine dependence 3.5 years later,» said Wong.