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Mutations in the genes for clotting factor VIII and IX cause hemophilia A and B, respectively. A woman may be heterozygous for mutations in both genes, with a mutated factor VIII allele on one X chromosome, and a mutated factor IX allele on the other. All of her sons should have either hemophilia A or B. However, on rare occasions, one of these women gives birth to a son who does not have hemophilia, and his one X chromosome does not have either mutated allele. Explain.
Chapter 14, Problem 9(choose chapter or problem)
Questions & Answers
QUESTION: Mutations in the genes for clotting factor VIII and IX cause hemophilia A and B, respectively. A woman may be heterozygous for mutations in both genes, with a mutated factor VIII allele on one X chromosome, and a mutated factor IX allele on the other. All of her sons should have either hemophilia A or B. However, on rare occasions, one of these women gives birth to a son who does not have hemophilia, and his one X chromosome does not have either mutated allele. Explain.
ANSWER:Step 1 of 3
Mutations in the genes for clotting factor VIII and IX cause hemophilia A and B, respectively. A woman can be heterozygous for mutations in both genes, meaning she carries a mutated factor VIII allele on one X chromosome and a mutated factor IX allele on the other.