Gene Helps Determine Time You Wake Up — And the Time of Day You’re Likely to Die

Scientists have been studying the gene responsible for the body's circadian (biological) clock for quite some time now, but made a bit of a breakthrough recently.  This gene, called Period 1, has variants of either two adenine (A) nucleotides, two guanine (G) nucleotides, or a mix of one of each which varies the clock rhythm.  (The reason for two nucleotides is because there are two sets of chromosomes, so the nucleotide of that specific allele of each chromosome is accounted for as either adenine or guanine.)  A person's natural sleep schedule, "times of peak cognitive performance, and the timing of many physiological processes" are affected by Period 1, including "times of the day when a person is most alert, when blood pressure is highest, and when the heart is most efficient," as well.  Now knowing this information can aid in one's health more so than before; if a person is found to have his/her highest blood pressure at noon, medication can be given shortly beforehand, or the person will make a better attempt to stay away from added stress around noontime.

Two studies were conducted, one with 1,200 65-year-olds and the other with volunteers of a younger generation.  These studies were compared and drew the same results.  The people with A-A at the allele of the Period 1 gene all wake up about an hour earlier than the people with the G-G nucleotides.  People with a combination of both A and G wake up at some point between the other two groups.  These variants not only distinguish a person's sleep habits, but also when the gene is expressed in the brain and white blood cells.  The most unbelievable factor of the research was that the variants help determine what time of day a person will die (of natural causes).  Those with A-A or A-G genotypes died just before 11 A.M., while the people with G-G genotypes passed away around 6 P.M.

 

It seems quite shocking that variants of just one gene consisting of two nucleotides can account for so many of life's important processes.  Sure, I would expect the typical sleep schedule associated with the circadian rhythm to be controlled by genes, but I was astonished at how such variants could even be held responsible for a person's time of death.  I feel that scientists will never cease to make new discoveries in genetics.  The fact that genes can turn on or off or posses a great deal of different variants makes tracking down all their different functions next to impossible.  I think whenever new roles are found for certain genes, I will still be just as surprised each time around.