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QuestionModerator: BioTeam
9 posts • Page 1 of 1
Colour Blindness is an X-linked recessive trait. If a female has normal vision, and to have colour-bind children, she would either have to be a carrier of the recessive gene, and/or be married to a colour blind male.
For example, a cross between a colour-blind male (XrY) and a normal vision woman who is a carrier (XRXr) could have four possible offspring combinations. 1. Colour-blind male(XrY) - 1/4 or 25% 2. Normal Vision Boy(XRY) - 1/4 or 25% 3. Colour-blind female(XrXr) - 1/4 or 25% 4. Normal Vision Female carrier (XRXr) - 1/4 or 25% However, since it is a sex-linked disease carried on the X chromosome, if the female does not have the colour-blindness allele at all, there is no way any of her children will be colourblind (though any female daughters will be carriers). I hope this helps.
Re: Question
Colour blindness is a X-linked recessive condition... In this case the parents alleles are: Mother : XX (not a carrier) vs. Father: XcY (sufferer of disease) Offspring with be: 2 x Female carriers (XcX) 2 x Normal Males (XY) So none of your answers are correct... In this case, none of the children would be colour blind...
Yes, exactly...
9 posts • Page 1 of 1
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