Color blindness, or color vision deficiency, is the inability or decreased ability to see color, or perceive color differences, under normal lighting conditions. Color blindness affects a significant percentage of the population. There is no actual blindness but there is a deficiency of color vision. The most usual cause is a fault in the development of one or more sets of retinal cones that perceive color in light and transmit that information to the optic nerve. This type of color blindness is usually a sex-linked condition. The genes that produce photopigments are carried on the X chromosome; if some of these genes are missing or damaged, color blindness will be expressed in males with a higher probability than in females because males only have one X chromosome, whereas females have two and a functional gene on only one of the X chromosomes is sufficient to yield the necessary photopigments. Color blindness can also be produced by physical or chemical damage to the eye, the optic nerve, or parts of the brain. For example, people with Achromatopsia suffer from a completely different disorder but are nevertheless unable to see colors.
HOW IS COLOR BLINDNESS DIAGNOSED?
Diagnosis can be done by a general physician who would ask you to name colors placed in front of you. In some cases, eye tests can also be prescribed. The Ishihara Plate test is the most common of the lot.
HOW IS COLOR BLINDNESS TREATED?
There is no cure for colour blindness. However, people with red-green colour blindness may be able to use a special set of lenses to help them perceive colours more accurately. These lenses can only be used outdoors under bright lighting conditions. Visual aids have also been developed to help people cope with colour blindness. For acquired colour vision deficiency, once the cause has been identified and treated, the vision may return to normal.
DID YOU KNOW?
This is a genetic problem and usually passes on. So if your mother had it and you got it, chances are that your kid will get it too.