Most colour blindness is hereditary. The faulty ‘gene’ for colour blindness is found only on the X chromosome. You have two X chromosomes if you are female or an X and a Y chromosome if you are male. It is because females have two copies of the X chromosome that they are far less likely to be colour blind. A male inherits his X chromosome from his mother and his Y chromosome from his father. So men do not inherit colour blindness from their fathers but from their mothers who can be carriers if they have one faulty X chromosome. Snoooooooooze. Probably you are bored reading this. The real point of this post is to say that Bradford University in the UK are studying colour blindness and are seeking females who are not colour blind but who have a child or a sibling who is. If this sounds like you please get involved in the study, help someone get their PhD, and maybe find out something interesting and useful. For more details see here.