Color blindness comes as a result of a lack of one or more of the types of color receptors. Most color perception defects are for red or green or both. About 10% of males have a color perception defect, but this is rare in females. Red-green color blindness is a result of a lack of red receptors. Another form of color blindness — yellow-blue is the second most common form, but it’s extremely rare. It is also possible to have the color receptors missing entirely, which would result in black and white vision.
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