Rs2814778

rs2814778 is within the DARC gene, which encodes the Duffy blood group antigen. This SNP shows an almost perfectly fixed difference in frequency between Europeans and those with African ancestry. (One exception appears to be a certain population of Czech gypsies, and certain non-Ashkenazi Jewish populations.) Additionally the Namibian San samples of the CEPH-HGDP are, uncharacteristically for Africans, all AA homozygotes for this SNP.

The rs2814778 (G) allele is associated with African populations, while rs2814778 (A) is associated with European populations and southwestern Native American populations.

rs2814778(G;G) protect against Plasmodium vivax malaria and predicts of white blood cell and neutrophil count

23andMe blog discussion

Malaria Resistance (Duffy Antigen)