Question

In humans, the allele for red-green color blindness is X-linked and recessive (Xr; the dominant allele is called XR). A man with normal color vision marries a color-blind woman who gives birth to a color-blind daughter. What can be inferred from this information?

Answer 1

Answer:

It concludes that the man is not the real father of the girl child.

Explanation:

Sex-linked or the X linked characters are the traits that inherited in a change or mutation in X chromosomes that cause the phenotype change in the male, which are homozygous for the gene as only possess one X chromosome and one Y chromosome, and Females if they are homozygous for the gene.

In the question, Man has a normal color vision (XrY) that means he has no mutated allele of color blindness. female has color blindness so that means she is a homozygous chromosome for the gene. Cross between these two results in 50% carrier daughters (XrXR) and 50% color blindness son (XRY). It means there is no chance for the color blind daughter.

Thus, the correct answer would be the man is not the real father of the girl child.