Tell Me Why?

Hemophilia (hee-muh-fil-ee-uh), is a hereditary bleeding disorder. This inherited condition results from the lack of particular clotting factors (a clotting protein) in the blood. The clotting factors are responsible to stop the bleeding when a blood vessel is torn by an injury. Clotting factors work together with platelets (thrombocytes ) to help the blood clot. Platelets (small cell fragments in the blood) function is to stop bleeding by sticking together to plug cuts and breaks at the site of the injury. The clotting factors (proteins) combine with the platelets to form fibrinogen which makes fibers (a net structure) that will stop the bleeding and allow the injured blood vessel to heal.

There are two main types of hemophilia (UK spelling: heamophilia) : hemophilia A (classical hemophilia, or Factor VIII deficiency) and hemophilia B (Christmas disease, or Factor IX deficiency). Hemophilia C has a lack of the clotting Factor XI. Clotting factors is identified by Roman numerals - Factor VIII, IX, X, XI. Hemophilia A is the most common form, where it is observed in ninety (90) percent of hemophiliacs followed secondly by hemophilia B.

Hemophilia occurs almost exclusively in men and boys, in which the blood clots much more slowly than normal, resulting in an extensive bleeding from even minor injuries. People with severe hemophilia are at risk of having life-threatening internal bleeding, whether they have been injured or not. They can also suffer from excessive bleeding caused by trauma and bruises.

Hemophilia is linked to a recessive gene on the X-chromosome whereby the disease is carried through the female but affects only male offspring. That is, it affects males while females on the other hand, act as carriers - passing on this defect in the genes from mother to son. These genes are located on the X chromosomes (a thread like structure that contain many genes which make a long continuous molecule of tightly coiled DNA). Females have two X chromosomes (X X ) and males have one X and one Y chromosome. Males get an X chromosome from their mother and a Y chromosome from their father. Females get an X chromosome from their mother and a X chromosome from their father.

A female who is a “carrier” of hemophilia, has the abnormal (defected) gene on one of her X chromosomes. This is because the other X chromosome carries the genes responsible for production of factor VIII or factor IX (clotting factors). The female will therefore will not have or suffer from this illness. For this this to happen both X chromosomes must have the abnormal gene which is very rare - It can happen for example, if the female father has hemophilia and her mother is a carrier. A male who has the abnormal gene on his X chromosome will have hemophilia. A male on the other hand, who has the abnormal (defected) gene on his X chromosome will have hemophilia. This is due to the fact that the Y-chromosome has no gene for factors VIII or IX that can compensate for the X chromosome deficiency.

Hemophilia can be mild, moderate, or severe. This will however depend on the amount of clotting factor that is present in the blood. Diagnosis for the disease will require several blood tests that includes a complete blood count (CBC), activated partial thromboplastin time (PTT), prothrombin time (PT), as well as, the level of the amount of factor VIII and factor IX present in the blood.

The general signs and symptoms of hemophilia are excessive bleeding and easy bruising of the skin. It can be internal or external. Excessive bleeding can be for example, from the mouth, nose, knees, elbows and other joints, as well as, from the kidneys, bladder, intestines, stomach and brain. There is no cure at present for hemophilia. The main treatment for hemophilia is done by regular injections of the deficient clotting factor ( factor VIII in haemophilia A or factor IX in hemophilia B).

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