What Is Hemophilia?

by Susan Flantzer © Unofficial Royalty 2012

Hemophilia is a genetic disease that prevents the blood from clotting properly. A hemophiliac will not bleed more profusely or more quickly than other people but will bleed for a longer time. External bleeding is usually not serious, but internal bleeding can be very problematic. There can be bleeding in joints, especially knees, ankles and elbows, and in tissues and muscles. When bleeding occurs in a vital organ, especially the brain, a hemophiliac’s life is in danger.

Hemophilia is transmitted on the X chromosome and it is a recessive trait. Women have XX chromosomes and men have XY chromosomes. Each person gets one chromosome from each parent. A woman has XX chromosome, so she can only pass an X chromosome on to her children. A man has XY and can pass either chromosome on, so the father determines the child’s sex. If the father passes the X, it’s a girl and if the father passes the Y, it’s a boy.

  • Children of a  Carrier Mother (XXH)  and a Normal Father (XY): 50% chance of sons having hemophilia, 50% chance of daughters being carriers
  • This is the model for the female descendants of Queen Victoria who were carriers.
Father  X Father Y
Mother XH XXH   (female carrier) XHY (male hemophiliac)
Mother X XX   (normal female) XY  (normal male)
  • Children of a Normal Mother (XX) and a Hemophiliac Father (XHY): all sons are normal, all daughters are carriers
  • This is the model for Prince Leopold, Duke of Albany, Queen Victoria’s hemophiliac son, and her only hemophiliac descendant to have children.
Father  XH Father Y
Mother X X XH (female carrier) XY (normal male)
Mother X X XH (female carrier) XY (normal male)
  • Children of a Carrier Mother (X XH) and a Hemophiliac Father (XHY): 50% chance of sons having hemophilia, all daughters are carriers, 50% chance of daughters having hemophilia (the ones with XH XH))
  • There are no examples of this model in Queen Victoria’s descendants. It is the only way for there to be a female hemophiliac.
Father  XH Father Y
Mother XH  XH XH (female carrier and hemophiliac) XH Y (male hemophiliac)
Mother X XXH  (female carrier) XY  (normal male)

When a woman is a hemophilia carrier, the hemophilia gene will be on only one of her chromosomes, so the carrier mother has a 50% chance of passing on the chromosome with hemophilia. If she passes the chromosome on to a daughter, that daughter will be a carrier. The daughter will not have hemophilia because she has a healthy X chromosome from her father. However, if the mother passes that X chromosome on to a boy, he will be a hemophiliac. A hemophiliac’s sons will not have hemophilia because the hemophiliac father will pass on a Y chromosome and his wife will pass on a healthy X chromosome. The daughter of a hemophiliac will always be a carrier because her father can only pass on an X chromosome with hemophilia on it. The only way for a female to be a hemophiliac is for her to be the daughter of a carrier and a hemophiliac.

hemophilia1

Chart from http://www.genetic-diseases.net/hemophilia-syndrome/

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Works Cited for Hemophilia Articles

  • Aronova-Tiuntseva, Yelena, and Clyde Freeman Herreid. “Hemophilia: The Royal Disease.” National Center for Case Study Teaching in Science. University at Buffalo, State University of New York., Web. 7 Apr. 2012.
  • “Haemophilia in European royalty.” Wikipedia. Web. 7 Apr. 2012.
  • “Hemophilia.” Genetic Diseases. Web. 7 Apr. 2012.
  • “Hemophilia B.” PubMed Health. U.S. National Library of Medicine, Web. 7 Apr. 2012.
  • “History of Hemophilia.” Hemophilia Information.com. Homecare for the Cure, Web. 7 Apr. 2012.
  • Eilers Koenig, Marlene, 2020. Hemophilia And Queen Victoria. [online] Royalmusingsblogspotcom.blogspot.com. Available at: <https://royalmusingsblogspotcom.blogspot.com/2019/08/hemophilia-and-queen-victoria.html?fbclid=IwAR3mL87V_4CQG9hQd7VwDk-M8Z1Oc1EmUHTj2G74z4dzQz6M7aBlXxdfdt8> [Accessed 24 July 2020].
  • Price, Michael. “Case Closed: Famous Royals Suffered From Hemophilia.” Science. Web. 7 Apr. 2012.
  • Raymond, Allan. “Haemophilia in Queen Victoria’s Descendants.” Monarchies of Europe. Web. 7 Apr. 2012.
  • Rogaev, E., Grigorenko, A., Faskhutdinova, G., Kittler, E. and Moliaka, Y. (2009). Genotype Analysis Identifies the Cause of the “Royal Disease”.
  • Zeepvat, Charlotte. Prince Leopold: The Untold Story of Queen Victoria’s Youngest Son. Phoenix Mill, UK: Sutton Publishing Limited, 1998. Print.