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Mystery #3Tier 3genetics chromosomes vision

Why are boys far more likely to be colour-blind than girls?

In a classroom, it is nearly always a boy who muddles up the red and green crayons. Colour blindness, where certain colours look alike, is far more common in boys than in girls. The eyes of boys and girls look exactly the same from the outside. So why does this land so unevenly?

A colour vision test plate: a circle filled with green dots with a number picked out in red and orange dots of similar brightness.
Photo: Shinobu Ishihara · Public domain · via Wikimedia Commons

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Why do you think boys are caught out by this so much more often?

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