Sickle Cell Disease is an inherited disorder of red blood cells, called erythrocytes, and the most common genetic disease in the United States. Normal red blood cells are round and concave in the middle; they flow easily through the bloodstream. Diseased erythrocytes, on the other hand, are sticky and bent into a sickle shape, like the sharp implements that are used to cut through sugar cane. Sickle cell anemia prevention is best discussed with a genetic counselor.
Both parents must carry the sickle cell trait for hemoglobin (Type AS) for the offspring to inherit the disease. If this is the case, there is a 25% chance that the child will have the disease, 50% chance that he or she will carry the trait and a 25% chance that they will have neither the trait nor the disease. If one parent has normal hemoglobin (Type AA) and the other has Type AS, there is a 50% chance that each child will carry the trait, but they will not get the disease.
While it is true that African Americans are more commonly affected by the disease than people of other nationalities, it does affect people of Latin American, Italian, Arabic, Greek and Asiatic Indian descent. In fact, people of Hispanic origin are half as likely to get SCD as someone of African American origin. Approximately 1 in 10 African American newborns have the trait and one in roughly 450 develop SCD.
If the gene for this disease is recessive, which it is, how did it get spread so widely through certain populations? This is because people who carry the trait have a tolerance to malaria, a deadly parasitic disease transmitted by mosquito bites in certain regions of the world. For a long time, the reason why people who have a selective advantage was unknown.
A recent publication in the scientific journal, Cell, indicates that, finally, the molecular reasons for this are beginning to be unraveled. This is good news for most of the world, half of whom are affected by this deadly disease. It is not, sadly, much help for those affected by sickle cell.
Many of the signs and symptoms of the disease are related to the anemia. These include fatigue, dizziness, headaches, shortness of breath, cold hands and feet, paler than normal skin and jaundiced eyes. Sickle cell disease is often punctuated by crises, in which the subject is suddenly in severe pain throughout the body.
A sickle cell crisis also affects the major organs (lungs, liver and kidneys). This, and the widespread pain in the limbs, is caused when the oddly-shaped blood cells block blood flow, causing pain and organ damage. The pain may last for several hours or persist for a week or longer.
All newborns in the United States are routinely tested for AS. This opens the door for early treatment of the disease. At the moment, the only way to prevent sickle cell disease is through genetic counseling and family planning. Research is ongoing to find ways of making it possible for individuals who have the disease to live comfortable and productive lives.
Both parents must carry the sickle cell trait for hemoglobin (Type AS) for the offspring to inherit the disease. If this is the case, there is a 25% chance that the child will have the disease, 50% chance that he or she will carry the trait and a 25% chance that they will have neither the trait nor the disease. If one parent has normal hemoglobin (Type AA) and the other has Type AS, there is a 50% chance that each child will carry the trait, but they will not get the disease.
While it is true that African Americans are more commonly affected by the disease than people of other nationalities, it does affect people of Latin American, Italian, Arabic, Greek and Asiatic Indian descent. In fact, people of Hispanic origin are half as likely to get SCD as someone of African American origin. Approximately 1 in 10 African American newborns have the trait and one in roughly 450 develop SCD.
If the gene for this disease is recessive, which it is, how did it get spread so widely through certain populations? This is because people who carry the trait have a tolerance to malaria, a deadly parasitic disease transmitted by mosquito bites in certain regions of the world. For a long time, the reason why people who have a selective advantage was unknown.
A recent publication in the scientific journal, Cell, indicates that, finally, the molecular reasons for this are beginning to be unraveled. This is good news for most of the world, half of whom are affected by this deadly disease. It is not, sadly, much help for those affected by sickle cell.
Many of the signs and symptoms of the disease are related to the anemia. These include fatigue, dizziness, headaches, shortness of breath, cold hands and feet, paler than normal skin and jaundiced eyes. Sickle cell disease is often punctuated by crises, in which the subject is suddenly in severe pain throughout the body.
A sickle cell crisis also affects the major organs (lungs, liver and kidneys). This, and the widespread pain in the limbs, is caused when the oddly-shaped blood cells block blood flow, causing pain and organ damage. The pain may last for several hours or persist for a week or longer.
All newborns in the United States are routinely tested for AS. This opens the door for early treatment of the disease. At the moment, the only way to prevent sickle cell disease is through genetic counseling and family planning. Research is ongoing to find ways of making it possible for individuals who have the disease to live comfortable and productive lives.
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