Sickle cell anemia is a heritable disorder that results from a mutation in the gene for hemoglobin, the protein that carries oxygen from the lungs to the tissues. The disease affects many different cell types, leading to symptoms including pain and organ failure. It has no cure, but symptoms are alleviated through blood transfusions and bone marrow transplant.
Red Blood Cells
Of all the cells affected by sickle cell anemia, perhaps the most visibly changed are red blood cells. These cells, explain Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry," are made up of molecules of the protein hemoglobin, which bind to oxygen molecules in the lungs and release the oxygen at the tissues. The structure for the protein hemoglobin is encoded into genetic material, or DNA, such that if there's an error in an individual's DNA in the coding region for hemoglobin, the protein will be malformed. Misshapen hemoglobin leads to misshapen red blood cells, and in fact, sickled cells are smaller and more irregularly shaped than normal red blood cells. The sickled cells can't deliver oxygen as efficiently as normal red blood cells.
Body Cells
All the body cells are susceptible to damage as a result of sickle cell anemia. MedlinePlus, an informational website maintained by the U.S. National LIbrary of Medicine, notes that one of the major symptoms of sickle cell anemia occurs as a result of the irregular shape of red blood cells. The oddly-shaped cells tend to clump together in blood vessels, forming small clots. This keeps blood from passing through those vessels, and causes oxygen starvation of body cells dependent upon the clogged vessel. Sickle cell patients often experience pain as a result of their clogged blood vessels, and serious clots can lead to tissue death and organ failure.
Neurons
Neurons are cells specialized for communication. They make up the brain and nervous system. Because multicellular organisms like humans depend upon cell-to-cell communication in order to survive, the brain and nerves are very important to life and livelihood. Sickle cell anemia patients sometimes experience symptoms that indicate damage to the brain and nerves. The National Heart Lung and Blood Institute notes, for instance, that clots forming in the vessels of the brain can cause strokes, which occur when brain cells don't have access to oxygen and die. Dizziness is another indication of brain cell oxygen deprivation, and is common in sickle cell anemia patients. Individuals with the disease may also have cold or numb hands and feet, which indicate that there isn't sufficient blood reaching the nerves of the extremities.
References
- "Biochemistry"; Reginald Garrett, Ph.D. and Charles Grisham, Ph.D.; 2007
- MedlinePlus: Sickle Cell Anemia
- National Heart Lung and Blood Institute: Sickle Cell Anemia
