BIO & 160
Sickle Cell Anemia
Our discussion in class and in our textbook on point mutations was of particular interest to me. Sickle cell anemia is one point mutations that is of interest because it can help us understand how inherited mutations work, and eventually, hopefully, how to cure them. Sickle cell is found in disproportionate numbers in the African and Mediterranean populations. Its discovery and similar ones have also helped in developing the one gene- one polypeptide theory. Sickle cell anemia or as it is sometimes called: sickle- cell disease is more than just a point mutation. It is a heritable blood disorder ...view middle of the document...
In sickle cell, the RBCâ€™s only live 10 to 20 days. The bone marrow cannot make new red blood cells fast enough to replace the dying ones. A person with sickle cell anemia may also experience severe pain, fatigue, bacterial infections, and the possibility of stroke.
Sickle cell is caused by a point mutation in hemoglobin (beta-globin) which results in hemoglobin S. One of the amino acids on the beta-globin chain is not normal. Glutamic acid is replaced by Valine. People with the disease are born with two sickle cell genes, one from each parent. . If you only have one sickle cell gene, it's called sickle cell trait. About 1 in 12 African Americans has sickle cell trait. A blood test can show if you have the trait or anemia. If you inherit the hemoglobin S gene from one parent and normal hemoglobin (A) from your other parent, you will have sickle cell trait. People with sickle cell trait do not have the symptoms of sickle cell anemia. However, people who have sickle cell trait can pass the sickle hemoglobin gene on to their children
The good news is that the point mutation in sickle cell anemia occurs in hemoglobin which is easy to isolate. Hundreds of single amino acid mutations in beta-globin have been documented. Sickle cell anemia currently has no cure, but treatments can help with the symptoms and complications of the disease. Bone marrow and stem cell transplants may offer a cure for a small number of people. Due to improved treatments and care, people who have sickle cell anemia are now living into their forties or fifties, or longer.
1.Principles of Life, Hillis Sadava,Heller, Price. Freeman Publishing, 2010.
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