a woman is a carrier for a recessive x - linked genetic condition, and her husband does not possess the…

a woman is a carrier for a recessive x - linked genetic condition, and her husband does not possess the allele. what are the odds that the couples son will express the condition? 0% 25% 50% 100%

a woman is a carrier for a recessive x - linked genetic condition, and her husband does not possess the allele. what are the odds that the couples son will express the condition? 0% 25% 50% 100%

Answer

Explanation:

Step1: Understand X - linked inheritance

Females have XX chromosomes and males have XY. A carrier woman has one normal X chromosome ($X^+$) and one X chromosome with the recessive allele ($X^-$), so her genotype is $X^+X^-$. The husband has a normal X chromosome and a Y chromosome, so his genotype is $X^+Y$.

Step2: Determine possible genotypes of sons

When they have children, for sons, the Y chromosome comes from the father. The X chromosome comes from the mother. The possible X - chromosome contributions from the mother to a son are either $X^+$ or $X^-$. There is a 50% chance of getting $X^-$ from the mother.

Answer:

C. 50%