Hemophilia A is a disorder where the body does not contain VIII (FVIII) which is a crucial protein that is used for clotting blood. People with this disease usually bruise easily and when cut, bleed for a longer period of time than a person without the disease would. The bleeding can be internal, in joints and muscles and externally from minor cuts, dental hygiene or trauma. People with severe hemophilia are able to have continuous hemorrhage, which is when blood comes out of a damaged vessel.  Some symptoms of hemorrhage is: weakness, problems with joints (tingling, stiffness, pain, unable to move), headaches, vomiting and abdominal pain. This does not follow Mendelian Genetics.

HEMOPHILIA from Kouzelna on Vimeo.
This video isn’t in English, but it shows how in a normal person the plasma will cover the open wound to stop blood from bleeding out, but for people who have hemophilia, it’s not present.

Hemophilia in inherited from the X chromosomal recessive disorder. It causes the clotting plasma to be unable to fully cover up the wound and still bleed. Since it’s and X-linked recessive, if the mother would carry the disorder, the following are the four most likely results:

-A daughter who doesn’t carry the trait
-A daughter who does carry the trait
-A son who doesn’t have hemophilia
-A son who does have hemophilia

The daughter wouldn’t have hemophilia because the father will also pass down an X chromosome which will over right the disorder on the mother’s X chromosome since it’s recessive. There are chances that a daughter will be infected, but it’s rare and both parents needs to be carriers of the gene, and both pass down a chromosome that carries the gene for hemophilia.

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