A woman with normal blood clotting mates with a man who also has normal blood clotting. Their first child is a boy who has hemophilia. Tests show that the child's hemophilia is X-linked and that he has normal genetic inheritance. You can predict that if the couple has more children together, then it is likely that ____.

Question

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Hemophilia is an X-linked recessive disorder. Since the mother is a carrier (having a normal phenotype but carrying one allele for hemophilia), each son has a 50% chance of inheriting the X chromosome with the hemophilia allele from her and thus having hemophilia. Daughters, however, will not have hemophilia because they will inherit a normal X chromosome from their father, ensuring they have at least one normal allele.

A Woman with Normal Blood Clotting Mates with a Man