92.8k views
4 votes
Color-deficient vision is a sex-linked recessive trait in humans. Parents with

the following genotypes have a child:

XRX X XRY

What is the probability that the child will have color-deficient vision?

A. 0.50

B. 0.75

C. 0.25

D. 1.00

Color-deficient vision is a sex-linked recessive trait in humans. Parents with the-example-1
User Roganjosh
by
8.4k points

1 Answer

0 votes

In the given genotypes, "XRX" represents a normal vision allele on the X chromosome, and "Xr" represents a color-deficient allele on the X chromosome. "XRY" represents a normal vision allele on the X chromosome and a normal allele on the Y chromosome.

Since color-deficient vision is a sex-linked recessive trait, it is carried on the X chromosome. In order for a child to have color-deficient vision, they would need to inherit the color-deficient allele (Xr) from their mother and the normal allele (XRY) from their father.

The probability of the child being a carrier for color-deficient vision (heterozygous) is 0.5, and the probability of the child having color-deficient vision (homozygous) is 0.25.

Therefore, the probability that the child will have color-deficient vision is:

P(homozygous) + P(heterozygous) = 0.25 + 0.5 = 0.75

Therefore, the correct answer is B. 0.75.

User HCSF
by
8.0k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories