Jan. 28, 2008 -- Are you a "morning person" who shines early, or a"night person" who is sharper later in the day?
Chances are, you don't need a team of scientists to answer that question.But new research shows that your body clock may be wound, in part, by yourgenes.
European scientists studied skin cells from 11"larks" (morning people) and 17 "owls" (night people). Overall,the skin cells reflected participants' "lark" or "owl"tendencies.
For instance, the researchers conducted a lab test in which they made theskin cells glow, in test tubes, in time with their natural circadian rhythm.The skin cells from the morning people faded a little earlier than the nightpeople's skin cells.
Also, a certain body clock gene was more active in the night people, reportthe researchers, who includedprofessor Steven Brown, PhD, ofthe Laboratory of Chronobiology at Switzerland's University ofZurich.
But it's not all about biology.
Participants' skin cells didn't all behave exactly as predicted. They had awide range of circadian rhythms. So Brown's team concludes that a person'sbehavior -- such as staying up until the wee hours or rising at dawn -- alsoaffects whether they are morning people or night people.
The findings appear in this week's online early edition of Proceedings ofthe National Academy of Sciences.