Question

PLEASE HELP ASAP!!!

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.
Based on the information provided, which of the following statements is true about the 400,000 people living with hemophilia?

They are all males because females can only be carriers of the trait.
The males with the disorder can’t pass the trait to their daughters.
Due to the method of inheritance, the majority of those with the disorder are males.
The females affected with the disorder inherited the trait from their father.

Answer 1

Based on the information provided, the statement that is true about the 400,000 people living with hemophilia is this: Due to the method of inheritance, the majority of those with the disorder are males.

What is the true statement?

The true statement can be seen from the pattern of inheritance. We learn from the pedigree that the majority of the people in the family who are carriers of the disorder are females. These include Alice, Queen Victoria, Irene, and Alexandria.

However, the disorder was mostly expressed in the men. These include Leopold, Frederic, Wildemar, Henry, and Alexis. Thus, we can conclude that due to the method of inheritance, the majority of those with the disorder are males.