Why are more men color deficient than women?
Men are approximately16 times more likely to be color deficient than women. Approximately 8% of men and 0.5% of women have some degree of inherited color deficiency (200 million people worldwide). Red-green color deficiency is a hereditary disease, carried by the X chromosome of females. For this reason the daughter of a color deficient father can pass it to her sons. Women have two X-chromosomes and one defective X chromosome will be compensated for by the other non-defective. The chances of having two defective X-chromosomes are small.