Question

which allele combination represents a female who is a carrier for an x - linked recessive disorder?
○ x^rx^r
○ x^rx^r
○ x^ry
○ x^ry

Explanation:

• Females have two X chromosomes (\(XX\)). A carrier has one normal allele (\(X^{R}\)) and one recessive allele (\(X^{r}\)).
• \(X^{r}X^{r}\) is a female with the disorder (both recessive alleles).
• \(X^{R}Y\) is a male with the normal allele.
• \(X^{r}Y\) is a male with the disorder.

Answer:

\(X^{R}X^{r}\)