20 PTS + BRAINLIEST IF CORRECT
Hemophilia is a rare bleeding disease that is carried on the X-chromosome. More than 400,000 people worldwide live with this disease, 20,000 of those within the United States. It is commonly called the “royal disease” because Queen Victoria was known to be a carrier of the disease and passed the gene to other members of the royal family.
If a healthy individual who does not have hemophilia gets a small cut on their arm, it takes 2-8 minutes on average for clotting to occur and for the bleeding to stop. People suffering from hemophilia lack an essential blood-clotting protein in their blood plasma. If they get cut, it can take 30 minutes to 22 hours for the bleeding to stop. Excessive bleeding is a constant danger to individuals with hemophilia.


Figure 1 shows the pedigree of hemophilia in four generations of Queen Victoria’s family.

Pedigree showing 4 generations of queen Victoria’s family. On of queen Victoria’s son, Leopold, has hemophilia. One of queen Victoria’s daughters, Alice, is a carrier of the gene for hemophilia. Alice has children with a man that does not have hemophilia. 2 of Alice’s daughters, Alexandra and Irene, carry the gene for hemophilia and her son has hemophilia. Alexandra has a son, Alexis, with a man that does not have hemophilia. Alexis has hemophilia. Irene has 2 sons with a man that does not have hemophilia. Both sons have hemophilia.

Using the pedigree, which statement is true about Leopold’s family?

A. If Leopold had a second male child, that son would have inherited hemophilia.
B. Leopold’s daughter, Alice, is homozygous recessive for the hemophilia trait.
C. Leopold’s son can’t have a biological female child with hemophilia.
D. The mother of Leopold’s children must be a carrier of hemophilia because the daughter is a carrier.