Women see one color differently than do men: red. She sees crimson, burgundy, and tomato. He sees red. Just plain ol' red. Why? It turns out there's a perfectly good reason why men can't see what is so obvious to women: the many variations--some subtle, some bold--of the color red. Reuters reports that researchers from Arizona State University in Tempe have determined there is a gene that allows us to see the color red, and that gene comes in a high number of variations. Because the gene sits on the X chromosome--and women have two X chromosomes and so two copies of this gene, compared with only one for men--the gene aids women's ability to perceive the red-orange color spectrum. The study findings were reported in the American Journal of Human Genetics.
In an analysis of the DNA of 236 men from around the globe, researchers found that the gene that allows people to see the color red comes in an unusually high number of variations. And that may be a boon to women's color perception in particular, study co-author Dr. Brian C. Verrelli told Reuters Health.
That's because the gene, known as OPN1LW, sits on the X sex chromosome. Women have two X chromosomes, one from each parent, while men have one X and one Y chromosome. Because women have two different copies of the "red" gene, the fact that the gene can have so many variations means it may especially aid women's perception of the red-orange spectrum.
Past research into color-vision genes has focused largely on variations related to color blindness. The red gene routinely swaps bits of genetic material with its neighbor on the X chromosome, the "green" gene. Sometimes this exchange goes wrong and results in a defect that causes color blindness.
An estimated eight percent of men are color-blind, while few women have the condition because the odds are they will have at least one good copy of the red and green genes.
