Hemophilia 2 Essay, Research Paper
In the human body, each cell contains 23 pairs of chromosomes, one of each pair inherited through the egg from the mother and the other from the sperm of the father. Of these chromosomes, those that determine sex are X and Y. Females have XX and males have XY. In addition to information concerning sex, the X chromosomes carry determinants for a number of other features of the body, including the levels of factor Vlll and lX. If the genetic information determining factors Vlll and lX is defective, hemophilia results. As a result, the protein factors needed for normal blood clotting are effected.
In males, the single X chromosome can not compensate for the lack, and will show the defect. In females however, only one of the two chromosomes will be abnormal. In very rare cases however, she will have inherited two defective X chromosomes and herself will be a hemophiliac. If she is not affected and the gene is recessive, she is now classified as a carrier. In some cases, there is no previous record of hemophilia in the family. Male children who would be born with hemophilia would be the result of the mutation of the gene.
There are two types of hemophilia: Hemophilia A and Hemophilia B. Hemophilia A, also known as “Classical Hemophilia” is caused by a factor Vlll deficiency. This is the most common form of hemophilia. The second type of hemophilia, is Hemophilia B, and is sometimes referred to as the “Christmas Disease.” Hemophilia B is caused by a factor lX deficiency. Both types of hemophilia are characterized by prolonged episodes of bleeding, especially into joints, muscles, internal organs, or even brain hemorrhaging.
Hemophiliacs do not bleed harder of faster than a normal, unaffected person. Instead, they suffer from prolonged bleeding. The reason a hemophiliac will suffer from prolonged bleeding, is the inability of the blood to form clots. This is the result of the missing/ reduced clotting factors. When a normal person sustains a cut or wound, the platelets in their blood break apart and quickly form fibrin, which forms the clot. In hemophiliacs however, either the clotting factor Vlll or lX is reduced, thus making the hemophiliac unable to form an effective clot. A few of the warning signs of internal bleeding in hemophiliacs are: headaches, sleepiness, nausea, vomiting, unequal pupil size, slurred speech, and disorientation and confusion.
Hemophilia is classified as severe, moderate, or mild, which indicates the expected frequency of bleeding. The normal clotting factor levels are on average 40% to 200%. If a hemophiliac has less than 2% clotting factors, then they are said to have severe hemophilia. If a person has severe hemophilia, factor Vlll of lX, depending on the type of hemophilia the hemophiliac suffers from, they will need the clotting factor Vlll or lX replaced several times a month, as a result of traumatic or apparently spontaneous bleeding. If a person suffers from moderate hemophilia, their clotting factors are 2% to 5%. Moderate hemophiliacs will experience less frequent bleeding, which is usually the result of trauma, surgery, or dental work. Hemophiliacs who suffer from mild hemophilia have clotting factors of 5% to 40%. They will experience only occasional bleeding, usually following severe trauma or surgery.
Hemophilia is basically treated by replacing the missing clotting factors. This is done by transfusing the missing clotting factors. The concentrates of the clotting factors are either manufactured from fresh frozen plasma and cryoprecipate, or are “freeze dried” factor Vlll and factor lX concentrates. The fresh frozen plasma and cryoprecipate are acquired from single blood donors and they require special freezing.
Factor inhibitors develop in 15% of males with Hemophilia A, but this is rare with Hemophilia B. Inhibitors are antibodies which neutralize the infused coagulation factor. This is a serious problem, because infusion of factor Vlll or lX is then considered ineffective.
The concentrates previously mentioned are manufactured in large quantities and they are packaged in small bottles. The bottles can be stored in either the fridge or at room temperature for home therapy. The newest and most expensive concentrates are made from recombinant gene technology. The recombinant portion is manufactured from some human blood components, but also from other animal biological components.
Scientists use a couple tools to try and determine whether a person will be a hemophiliac, a carrier, or normal. The first device is called a pedigree. This is simply a well organized chart which displays the whole family and which person had what. Carriers are identified with their whole shape being shaded in. Family members who have no signs of the disease at all have their whole space blank. Another tool which scientists use, is called a Punnett Square. This shows the possible child births of a couple. The males chromosomes (X and Y) are located at the top of the diagram. The females chromosomes (X and X) are located along the left hand side of the diagram. Here is an example:
This diagrams demonstrates the birth of a Xh Y
child between a hemophiliac male and a
normal female. The males defective x X XhX XY
chromosome will be passed to a daughter
no matter what, so she will in the end be X XhX XY
a carrier. If a male child is to be born
though, he will not be a hemophiliac,
because he has inherited either one of his
mother’s X chromosomes, and neither of
her X chromosomes were infected.
Hemophilia is not always fatal. Many hemophiliacs survive a very long time and lead prosperous lives. For a very long time, hemophiliacs had to travel to hospitals regularly for clotting factor transfusions. Courtesy of new medical advances, many hemophiliacs are now able to treat their disease in the privacy of their own home. Hemophiliacs lead long, happy lives exactly the same as the rest of us do.