HP and anemia (phenotype): Prior biological knowledge of the high affinity specific interaction of haptoglobin with free hemoglobin (its main role) [20], together with a publication showing an association of the severity of anemia with haptoglobin genotype in patients infected with malaria [21] and on reporting an association of free hemoglobin level with haptoglobin genotype [12], led us to hypothesise that HP would be associated with hemoglobin in the direction that we observed.