For example, we found recently that the disease-accelerating effects of the CCL5 -471A/A genotype in African Americans is evident only in those who do not bear the African-specific -46C/C genotype of Duffy Antigen Receptor for Chemokines (DARC), a genotype which is thought to have arisen due to the selective pressure of specific malaria-causing species [43]. This evidence concerns the gene CCL5 and malaria.