Hemophilia is a sex-linked recessive disease. A mother who is a carrier of the disease mates a healthy male. Which of the following statements is true?

Explanation

In the given scenario where a mother is a carrier of the sex-linked recessive disease hemophilia and mates with a healthy man, the following statement is true: 50% of sons will have hemophilia. Hemophilia is an X-linked recessive disorder, which means the gene responsible for hemophilia is located on the X chromosome. Females have two X chromosomes (XX), while males have one X and one Y chromosome (XY). When a carrier mother (XhX) mates with a healthy man (XY), the possible outcomes for their offspring are as follows: Sons: There is a 50% chance that a son will inherit the X chromosome with the hemophilia allele (Xh) from the carrier mother, resulting in the son having hemophilia (XhY). There is also a 50% chance that a son will inherit the healthy X chromosome from the mother (X) and the Y chromosome from the father (Y), resulting in the son being unaffected by hemophilia (XY). Daughters: There is a 50% chance that a daughter will inherit the X chromosome with the hemophilia allele (Xh) from the carrier mother and a healthy X chromosome from the father (XhX). Therefore, the correct statement is that 50% of sons will have hemophilia.