Welcome aboard @Thomas Birkett

Welcome aboard @Mickey Galloway

Colour blindness is linked to the X chromosome. If it has the bad gene on the X chromosome, a male has colour blindness. In a female, both X chromosomes need to have the damaged gene for the colour blindness to kick in. Yes, the most common form of the condition (red-green colour blindness) is inherited via the X chromosome. This is why it is much more common in biological males than in biological females. - How it affects males (\(XY\)): Males only have one X chromosome. If that X chromosome carries the gene mutation for colour blindness, they will be colour blind. - How it affects females (\(XX\)): Females have two X chromosomes. For a female to be colour blind, both of her X chromosomes must carry the mutated gene. If she only has one mutated gene, the other healthy X chromosome compensates, making her a carrier rather than colour blind herself. I did remember a few things from studying genetics in the 70s!

Thank you Dave.