The sickle cell gene is passed on from generation to generation. Typically red blood cells are disc shaped. In persons with sickle cell, also known as sickle cell anemia, the red blood cells are disc shaped (hemoglobin A), as are some that are shaped like a crescent (hemoglobin S, the S standing for sickle). According to the Mayo Clinic, sickle cells break apart much more easily than the disc-shaped hemoglobin A blood cells. A normal blood cell will live for around 120 days. Sickle cells generally only last for 10 to 20 days, so those with the disease are often short of red blood cells, which causes chronic fatigue.
Genetic Mutation
Sickle cell is caused by a mutation in the gene responsible for directing your body to produce hemoglobin. Hemoglobin is the substance responsible for moving oxygen through your red blood cells to different parts of your body. It also carries carbon dioxide from throughout your body to the lungs, where it can be exhaled. In someone with sickle cell, the gene mutates the hemoglobin so that the blood cell is produced in a crescent shape.
Heredity
Sickle cell is passed down from one generation to the next. Both the mother and father have to have the sickle cell trait in order to hand the gene mutation down to the next generation and cause sickle cell anemia. If only one parent has the sickle cell trait, then the offspring of that couple would have the trait, but not the actual disease. In people with the sickle cell trait, their bodies still produce sickle cells, but it's generally not enough to manifest itself in physical symptoms. One other thing to note is that, according to the Mayo Clinic, when both parents have the trait, there is only a 25 percent chance that their offspring will have sickle cell anemia.
Genetic Origins
Sickle cell can affect anyone born of two parents with the sickle cell trait. It is interesting to note that it is more common among those with African, Spanish, Mediterranean, Middle Eastern and Indian ancestry. In the United States, sickle cell is most common in African-Americans and those of Mexican descent.
