The sun never sets. For the moment, no.


Tracking your internal clock may be as easy as plucking a few strands of hair, according to a new study.

The research found that hair follicles hold a record of the gene activity that influences when we wake and when we sleep. The results could be used to diagnose and study sleep disorders and conditions like jet lag.

Whether you’re a night owl or a morning lark, your sleep-wake cycle is controlled in large part by genes called clock genes. These genes vary their activity throughout the day, setting the internal clock that drives our circadian rhythms.

The first human clock gene was discovered almost 10 years ago, but isolating the genes efficiently enough to study sleep-wake cycles in real time has proved difficult. When the genes are active, they transcribe their DNA into RNA, the first step in producing various proteins that essentially carry out a gene’s instructions and, in this case, influence circadian rhythms. The RNA can be found in cells all over the body, from white blood cells to the lining of the mouth, but techniques for extracting it from these cells proved unreliable.

{ LiveScience | Continue reading }