Sex-linked traits

In Drosophila flies, eye color is sex-linked. The allele for red eyes (X${}^{\text{W}}$‍) is dominant to the allele for white eyes (X${}^{\text{w}}$‍).

A male fly with red eyes X${}^{\text{W}}$‍Y and a carrier female X${}^{\text{W}}$‍X${}^{\text{w}}$‍ are mated.