Red-green color blindness is a sex-linked recessive trait in humans. two people with normal color vision have a color-blind son. what are the genotypes of the parents?

The genotype of the mother is XX while the genotype of the father is XY.

A genotype simply means the collection of genes in an individual. It is also referred to as the alleles that are inherited in a particular gene.

In this case, since red-green color blindness is a recessive trait, this implies that it will not be visible in a heterozygous female. Hence, the dominant allele will therefore mask the recessive allele.

Since the father has only one X chromosome, then if the trait was present in that X chromosome, he must have shown the trait because all the alleles in Y chromosome are recessive. In this case, the son has inherited the trait from the mother.

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Genotype of Mother: XX°

Genotype of Father: XY

Explanation: