Haemoglobin C results from a variation in the gene that codes for haemoglobin, the protein in our red blood cells that helps carry oxygen around the body. It causes anaemia in people who have inherited the haemoglobin C (HbC) gene from both parents and can also provide a degree of protection against malaria infection.
Individuals who have inherited the HbC gene from only one parent are carriers of the gene but one copy alone does not cause anaemia. Carriers with just one copy of the HbC gene have a degree of protection against developing severe malaria.
We have created a contemporary map of distribution of the HbC gene and have used this to provide estimates of the numbers of newborns affected at various geographical scales.