Malariais a potentially life-threatening disease because of a parasite from thePlasmodiumgenus.
This parasite is spread through the bite of a femaleAnophelesmosquito.
Over time, some red blood cell disorders have evolved to help reduce the severity of malaria.
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This article will review the connection between sickle cell trait and how it protects against malaria.
After these cells rupture, the parasite infects red blood cells.
These infected red blood cells travel through the blood vessels.
The parasites turn the cells' oxygen-transporting protein hemoglobin into a toxic form.
When the RBCs burst, they dump wastes and toxins into the blood.
These can cause significant symptoms in an affected person, which can lead to death if untreated.
Sickle Cell Disease
Sickle cell diseaseis an inherited genetic disorder that affects thehemoglobinmolecule in red blood cells.
Hemoglobin in RBCs transports oxygen from the lungs throughout the body.
In the small blood vessels, hemoglobin releases oxygen and binds carbon dioxide.
When the blood returns to the lungs, hemoglobin exchanges carbon dioxide for oxygen.
Normally, red blood cells are disk-shaped and flexible, allowing them to travel through small blood vessels.
It makes the RBC sticky, rigid, and forms a sickle shape.
Sickle cells can clog small blood vessels.
They also die early.
However, they can pass the sickle cell gene on to their children.
People living with the sickle cell trait have shown some resistance to severe forms of malaria.
This protection against malaria has kept the sickle cell gene mutation in the population.
How Common Is Sickle Cell Trait?
Sickle cell trait is found in up to 3 million Americans and up to 10% of African Americans.
The connection between sickle cell trait and malaria was first discovered in the 1940s.
How Does Sickle Cell Protect Against Malaria?
Children with sickle cell trait and malaria can reset the infection much quicker than those without sickle cell trait.
It has not been determined exactly how sickle cell trait protects against malaria.
Many reasons are likely, not just one.
The sickle cell trait is inherited when someone inherits one copy of the mutated gene.
This one copy doesnt cause sickle cell disease but can give some protection against malaria.
The areas of the world with the highest malaria rates also have the highest rates of sickle cell trait.
Frequently Asked Questions
The sickle cell mutation can offer protection against malaria.
Malaria is much more common in Africa.
Over time, this has resulted in the sickle cell mutation being more common in people in Africa.
Sickle cell anemia has an autosomal recessive inheritance.
Sickle cell trait means that someone inherits only one copy of the mutated gene.
This does not give them sickle cell anemia, and it can offer them protection against malaria.
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