Question

Colorblindness is a sex-linked recessive trait. If B=normal and b=colorblind, what would be the genotype of a normal male? Question 1 options: XbY XBYb XBXb XBY

Answer 1

Answer:

The Genotype of a normal male wil be: XBY.

Explanation:

• A sex linked recessive disorder is expressed only in males because males have only one X chromosome and so only one allele for this gene can be present in them.
• Hence, if the recessive allele is present then colour blindness will occur.
• If the dominant allele is present then the male will be normal.
• XbY has a recessive allele so the male with this genotype will be color blind.
• XBYb cannot be aoption because Y chromosome cannot have the allele of the gene.
• XBXb is a female carrier's genotype.
• XBY has the dominant allele and so the man with this genotype will be normal.