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Genetics and Inheritance

Treatment for cystic fibrosis

In 2005 the U.S food and drug administration approved the first DNA based blood test to help
detect CF. Other tests to help detect CF include: Sweat chloride test, which is the standard test for CF.
High salt levels in the patients sweat is an indication of CF, Fecal fat test, upper GI and small bowel
series, and measurements of pancreatic function. After a diagnosis has been made there are a number of
treatments available, these include: Antibiotics for respiratory infections, pancreatic enzyme
replacement, vitamin supplements (mostly A, D, E, and K), inhalers to open the airways, enzyme
replacement therapy which makes it easier to cough up the mucus, pain relievers, and in very severe
cases, lung transplants.

Sickle cell anemia

Sickle cell anemia is an inherited disease of the red blood cells which causes abnormally shaped
red cells. A typical red blood cell has about 270 million hemoglobin molecules, which bind with
oxygen. In a person with sickle cell disease, one amino acid is changed in the hemoglobin molecule,
and the end result is misshapen red blood cells. In a patient with sickle cell disease the red blood cells
change from the normal round shape to the shape of a sickle or "C" shaped. The abnormal shape causes
the cells to get stuck in some blood vessels which causes blockage in the vessel. This causes pain and
can destroy organs because of the lack of oxygen. Sickle cells live only 10 to 20 days and a normal cell
lives about 120 days.

This rapid death of blood cells leads to chronic anemia. Complications can include severe pain,
terrible infection, swelling of the feet and hands, stroke, damage to the eyes, and damaged body organs.
These effects can vary from person to person depending on the type of sickle cell disease they have.
Some patients are mostly healthy and others are in the hospital more than they are out. Thanks to
diagnosis and treatment advancements, most children born with sickle cell grow up to have a normal
and relatively healthy life. The form of sickle cell is determined by which genes they inherit from the
parents. When a child inherits a sickle cell gene (hemoglobin gene) from each parent it is called
hemoglobin SS disease ( which is the formal name for sickle cell). When a child inherits a sickle cell
gene from one parent and a different abnormal gene from the other parent, it is a form of disease called
hemoglobin SC disease or hemoglobin S-thalassemia. If a child inherits a normal gene from one parent
and a sickle cell gene from the other, the child will not have sickle cell but will be a carrier and may
pass it to their children. Sickle cell affects mostly African Americans and some Latino Americans. A
person who is a carrier (has one copy of the gene) is resistant to malaria. This heterozygote advantage
explains why the gene is more common in people in equatorial regions, or who are descendants of such
people (such as African Americans).

Treatment for Sickle cell anemia

Sickle cell is diagnosed at birth with a simple blood test. If the first blood test is positive then a
second test is done just for confirmation. Because of the high risk of infections that occur with sickle
cell, early diagnosis is very important. Other than a bone marrow transplant there is no known cure for
sickle cell. Bone marrow transplants have a high risk of rejection and aren't an available option for
every patient. The patient would need a bone marrow donor match with a low risk of rejection. Even
without a cure, with the use of pain medications and antibiotic treatments, children with sickle cell can
live a long and happy life. Blood transfusions are sometimes used to treat episodes of severe pain. For

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