title: Duffy blood types and vivax malaria in Ethiopia.
abstract: We investigated an hypothesis relating the Duffy-negative blood type with insusceptibility to vivax malaria--and previously associated only with people of West African ancestry--in three population samples of eastern African stock. The samples included Nilotic and Hamitic-Semitic residents of a malarious locale in Ethiopia and Hamito-Semites in Addis Ababa where malaria is not endemic. Fresh red blood cells from 191 subjects were tested with Duffy antisera, anti-Fya and anti-Fyb. Duffy-positive rates in the malarious community were 8% for the Nilotes and 70% for the Hamito-Semites; the Hamito-Semites in Addis Ababa were 98% Duffy-positive. The relative prevalences of Plasmodium vivax in the two study groups at risk to malaria were 2.4% for the Nilotes and 27.3% for the Hamito-Semites, producing a ratio similar to the ratio of Duffy-positive in the two samples. We interpret the data as supportive of the Duffy-vivax hypothesis with reference to a part of eastern Africa, and we suggest that the Duffy-negative genotype may represent the original, rather than the mutant, condition in tropial Africa.
mesh_terms: D000293:Adolescent; D000328:Adult; D001789:Blood Group Antigens / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D003710:Demography; D004375:Duffy Blood-Group System / Q000235:genetics*; D005002:Ethiopia; D005260:Female; D006801:Humans; D008288:Malaria / Q000097:blood*; D008297:Male; D010966:Plasmodium vivax; D044469:Racial Groups
chemical_list: D001789:Blood Group Antigens; D004375:Duffy Blood-Group System