Color Blind

Color blindness is a genetic condition that results in difficulty distinguishing certain colors from others, and sometimes a complete inability to see certain colors the way they would appear to everyone else. Since it is passed along in genes, it is present at birth and is incurable. It is much more common in men than it is in women, and some studies suggest that as many as one in twelve men are color blind.

The reason it is seen primarily in men is because the gene that codes for colorblindness is carried on the X chromosome. Since men only have one X chromosome, if they inherit an X chromosome coded with some kind of colorblindness they will be affected with the disorder. Women need to inherit two affected X chromosomes in order to display the disorder, and it is therefore extremely rare to see women who are color blind. Women with one affected X chromosome have normal vision, but they act as the ‘carriers’ for the trait, passing on the disorder to 50 percent of their male children. A male affected with color blindness will not pass on the disorder to any of his sons, but all of his daughters will be carriers for the trait.

One extremely common misconception is the belief that color blind people can’t see any colors whatsoever. The term color blind is something of a misnomer. Most forms of color blindness would be more accurately described as ‘color deficiencies’. Though there is such a form of color blindness that results in a complete inability to see any color, called monochromasy, it is extremely rare. More common versions of the disorder reduce the affected individuals ability to distinguish between two colors. The most common form is called deuteranopia and is a loss in the ability to distinguish reds and greens. Tritanopia, another common form of color blindness, is a deficiency in distinguishing blue and yellow.

Color blindness comes in varying degrees of severity as well. Only in the most severe cases is the ability to distinguish certain colors completely lost; usually people only have trouble with certain shades of the color. Because it can sometimes be very mild, it can actually be hard to determine if you are color blind or not. One popular test, called Ishihara plates, are often used to help diagnose the disorder. Many samples of Ishihara plates are available today online, as well as a multitude of other resources to help people determine if they are color blind or not.