A population genetic study on the Ag polymorphism in South African Indians and Negroids.

Two population samples from South Africa, i.e. 555 Bantu-speaking Negroids and 75 Indians, were tested for selected immunogenetic specificities comprising the Ag polymorphism. Within the Negroid sample a new Ag phenotype (i.e. the 49th) was discovered. Interpopulational comparisons involving the present two, as well as three previously studied samples, reveal characteristic differences in regard to the frequency distribution of Ag phenotypes, to the Ag allele frequencies and to the occurrence of Ag haplotypes. These results are discussed. All the data could be interpreted satisfactorily in terms of the genetic model regarding the Ag system as postulated by Bütler and his co-workers.