Why Men are More Prone to Colour Blindness

Red-green colour blindness affects approximately 8% of Northern European men, but only 0.5% of women with the same ancestry.

So why is it that this visual deficiency occurs among males so much more frequently?

The X Chromosome Mutation

While colour blindness could be a result of disease, trauma, or drug  toxicity, it’s most commonly a result of genetics.

The mutation for colour blindness is carried on the X chromosome. Females have two X chromosomes, so if they have one that is unaffected, they will only be carriers. To be at risk of inheriting the disorder, females would need both a carrier mother and an affected father. Conversely, males only have one X chromosome that is inherited from the mother’s side. If that chromosome is affected, the male child will be colour blind.

Complications of this hereditary condition may become more apparent as those afflicted grow older—for instance, their colour blindness may impact their choice of occupation or performance in certain tasks.