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Right-Handed? Your Hair Reveals It
If you want to know whether your newborn baby will be right-handed or left-handed, here's a way to tell that is almost fool-proof: Look at the baby's hair. If the hair swirls clockwise, there is a 95 percent chance that the person is right-handed. The curls of lefties and the ambidextrous are equally likely to coil either way.
What does your handedness have to do with your hair? This isn't some goofy New Age idea or parlor game, although it would be fun to try at parties since it also works on adults. Nature News and London's Evening Standard report that researchers from the National Cancer Institute in Frederick, Maryland have determined that one gene might control both hair swirl direction and handedness and in the process explain the divided brain. That has geneticists hunting for a single gene with either "right" or "random" forms. Those who have one or two copies of the "right" version of the gene would be right-handed and have hair that swirls clockwise. Those who have two "random" versions of the gene could be either right- or left-handed and have hair that swirls in either direction.
To arrive at this fascinating conclusion that your hairstyle determines your handedness, researcher Amar Klar of the National Cancer Institute had to be a little underhanded. He surreptitiously checked out the heads and hands of 500 people in airports and shopping malls. Anyone with long hair and those who were bald were not included in his survey.
What do other scientists think of this research? "It's one of the most exciting things [I've seen] in a while," geneticist Ralph Greenspan of the Neurosciences Institute in San Diego, Calif., exclaimed to Nature News. He suggests that a gene causing asymmetric cell division in the young embryo might set up asymmetry throughout the body. Others aren't so sure. Clyde Francks of the University of Oxford in Great Britain thinks there are many genes--not just one--that determine if we're right-handed or left-handed.
This gene hunt could be hard. Some think there may not even be a gene for handedness since two left-handed parents can have a right-handed kid. Or, in a set of identical twins, one could be right-handed and the other left-handed. Aha! Klar thinks he has this one solved. If the children of lefties inherit a "random" gene, they could be either right-handed or left-handed--so it's still genetically governed.
"It is certainly possible to make a very accurate guess at which hand somebody writes with by looking at their head," Klar told London's Evening Standard. "Medically, this is also important as it reveals a lot about how the brain develops and which parts of the body develop along with it. It is actually a very good indicator of brain symmetry." The research could one day help treat diseases caused by abnormalities in brain symmetry like autism, schizophrenia, and dyslexia.