SCD patients can transmit the illness or SCT on to their offspring. What Causes Sickle Cell Disease? SCT is caused by the inheritance of one sickle cell gene and one normal gene. This implies that while the individual will not have the disease, he or she will be a "carrier" who can pass it on to his or her offspring. Sickle cell anemia is the most common form of the disease.
Carriers may not know they are carriers because they do not have the sickle cell trait nor does anyone in their family history have the disease. About 1 in 25 blacks births are affected by SCD; this means that about 1 in 50 black babies are born with sickle cell disease. In addition, about 1 in 100 Hispanics and 1 in 200 Asians are carriers of sickle cell disease.
In general, individuals with SCD are at increased risk for complications from simple everyday activities such as playing sports or engaging in other physical activities. For example, someone with SCD might experience more severe pain than another person after being subjected to high levels of stress during exercise. The disease may also cause problems with major organs including the heart, lungs, and brain. A patient diagnosed with SCD should always consult with a physician before starting any exercise program.
People can become carriers of SCD if they have one copy of the mutated gene and one copy of the normal gene.
SCT is not a sickness, but it indicates that a person acquired the sickle cell gene from one of his or her parents. SCT patients often do not exhibit any of the signs of sickle cell disease (SCD) and lead normal lives. However, they are at increased risk for serious illness if they are exposed to low temperatures, have a blood transfusion, or receive multiple units of red blood cells.
The most common form of SCT is HbAS. People with this type of SCT have two copies of the hemoglobin S gene (SS) and therefore produce half as much normal hemoglobin (AA) as people without the trait. The severity of their anemia depends on how many S chromosomes they have. If a person has one S chromosome, he or she will produce only SS hemoglobin and will also be vulnerable to complications from SCD. If a person has two S chromosomes, he or she will produce only AA hemoglobin and are not at risk for SCD-related problems.
People with SCT are more likely to experience blood disorders caused by abnormal levels of certain proteins in blood. For example, patients may have IDA, which is caused by insufficient production of healthy red blood cells. They are also at risk for other diseases that increase their chance of infection, such as malaria and AIDS. Patients may need blood transfusions to replace blood cells that are destroyed by bacterial infections or trauma.
4 Sickle Cell Disease Facts You Should Be Aware Of
To have sickle cell trait implies to have a sickle cell anemia gene that can be handed on to one's offspring. As a carrier of this gene, your baby's red blood cells contain some sickle hemoglobin, although significantly less than a sickle cell anemia patient. The presence of these partially broken cells may lead to sickling of the whole blood sample during laboratory tests or after injury, causing pain-related events.
Carriers of the sickle cell trait are asymptomatic but may have increased risk of infections. There is no evidence that carriers of the sickle cell trait are at increased risk for heart disease or other health problems associated with sickle cell anemia.
Children of sickle cell trait carriers have a 1 in 4 chance of being a carrier themselves. They also have a 1 in 4 chance of being born with sickle cell anemia. Because of this high rate of inheritance, patients with sickle cell trait are often referred to as having "sickle cell disease." Although this term is commonly used, it is not accurate. Patients with sickle cell trait do not have sickle cell disease; they have a different genetic condition called hemoglobinopathy.
People with sickle cell trait should know their status and be informed about the risks of transmitting this trait to children. If a pregnant woman has sickle cell trait, her doctor may advise her to consider having prenatal screening for sickle cell anemia.
A individual with sickle cell trait (one sickle cell gene) is born with sickle cell trait and will always have sickle cell trait. The same may be said with sickle cell disease (two sickle cell genes). Sickle cell disease causes sickness, but sickle cell trait does not. The severity of sickle cell disease varies with time. Some people are born with two damaged copies of the gene, others are born with one normal copy and one damaged copy, and still others are born with two healthy copies.
Sickle cell disease affects people of African descent particularly in Africa and America. It is more common in individuals who are homozygous for the sickle cell allele (SS genotype). In other words, an individual must have two copies of the sickle cell allele to be affected by sickle cell disease. People with one copy of the sickle cell allele (AS or AA genotype) can develop a mild form of the disease known as sickle cell trait. Individuals with two copies of the normal hemoglobin gene (AA genotype) cannot get sickle cell disease because they do not have enough damaged genes to cause the disease. They would just have a very bad episode if they were to suffer a blood loss that could not be recovered from.
People with one copy of the sickle cell gene and another genetic mutation sometimes develop severe disease. This occurs when people with two copies of the mutant gene (CC genotype) also carry one copy of the sickle cell gene (SS genotype).