Answer :
colorblindness is caused by mutations in the genes. There are 3 color cones red, green and blue. when someone is colorblind there is usually a red or green cone missing.
The most common cause of color blindness is confusion between red and green. It is a genetic mutation. Very few people are totally color blind (ie they see in black and white only) - most seem to have some color vision but get confused between certain colors. Oh, and for some strange genetic reason, far more men are color blind than women.
