Haemoglobin C or hemoglobin C (spelling depends on which side of the Atlantic you belong) is a variant form of human hemoglobin, where the glutamate in the sixth position of the beta-chain is replaced by lysine. It is found most commonly in West Africa, and in some populations its prevalence may be as high as 25%.
There is good epidemiological evidence to show that haemoglobin C protects against falciparum malaria (Agarwal et al, 2000), which explains its high prevalence in West Africa. The mechanism of that protection is hypothesised to be due to an effect on PfEMP-1 presentation on erythrocytes (Fairhurst et al, 2005).
Haemoglobin SC disease occurs when a person is heterozygous for haemoglobin C and for haemoglobin S. The disease is clinically very similar to sickle cell disease.
References
- Agarwal et al (2000) Hemoglobin C associated with protection from severe malaria in the Godon of Mali. Blood 96:2358-2363.
- Fairhurst RM et al (2005) Abnormal display of PfEMP-1 on erythrocytes carrying haemoglobin C may protect against malaria