Scientists are unraveling the mystery of your body’s clock – and soon may be able to reset it

For people who don’t get sleepy until 2 a.m., the buzz of an alarm clock can feel mighty oppressive.

Relief may be on the horizon, thanks to the discovery this spring of a genetic mutation that causes night-owl behavior.

Whether you’re a night owl or a morning lark rising effortlessly each day with the sun, your sleep habits are regulated by circadian rhythms. These internal clocks control just about every aspect of our health, from appetite and sleep to cell division, hormone . . .