Question

If the white-eye trait were X-linked dominant, rather than X-linked recessive, what result would you expect when crossing a heterozygous white-eyed female with a white-eyed male?

Answer 1

In an X-linked dominant cross between a heterozygous white-eyed female (XWXw) and a white-eyed male (XWY), all offspring, regardless of gender, would exhibit the white-eye phenotype, leading to 100% white-eyed offspring.

Step-by-step explanation:

If the white-eye trait were X-linked dominant, rather than X-linked recessive, and we crossed a heterozygous white-eyed female (XWXw) with a white-eyed male (XWY), we would expect a different outcome than with recessive inheritance. Since the trait is dominant, any offspring inheriting the XW allele from either parent would show the white-eye phenotype. Therefore, all daughters (XWXW or XWXw) would be white-eyed because they will inherit at least one XW allele from one of their parents. All sons would be white-eyed (XWY), inheriting the XW from their mother and Y from their father. Thus, the result of this cross would yield 100% white-eyed offspring.