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Sickle Cell Anaemia and Malaria.
Sickle Cell Anaemia
It is a genetic disorder which is caused by a faulty allele which codes
for haemoglobin which carries the oxygen in the red blood cells.
Blood cells which have the different haemoglobin give the red blood
cells a sickle like shape. Instead of being round and spongy, the
blood cells are long and sharp.
This two diseases are linked. In many parts of Africa, Sickle Cell anaemia is more
common in areas where malaria is common.
Those who are sickle cell carriers (those who have only inherited one Sickle Cell
allele who doesn't feel the symptoms of the disease) are more immune to
Malaria than those who aren't.
They are more likely to survive in the high risk areas and reproduce to have
children passing on the sickle cell trait.
Therefore, the sickle cell allele is higher in areas of higher malaria rate.