Question

which allele combination represents a male who has an x - linked recessive disorder
○ xy
○ x^ry
○ xx
○ x^rx

Explanation:

• Males have the sex - chromosome combination \(XY\).
• For an X - linked recessive disorder, the allele on the X - chromosome is recessive. So the genotype is \(X^{r}Y\).
• \(X^{R}Y\) represents a male with the dominant allele on the X - chromosome.
• \(X^{r}X^{r}\) is a female genotype (two X - chromosomes).
• \(X^{R}X^{r}\) is also a female genotype (heterozygous).

Answer:

\(X^{r}Y\)