The M-N--V-A-B-D blood group system of chimpanzee and other apes: serology and genetics

Poly- and monoclonal anti-M and anti-N reagents detect on the red cells of anthropoid apes the M and/or N antigens which are similar to, but not identical with human M and N. A series of V-A-B-D specificities, closely related to the M-N system, are recognized on ape red blood cells by chimpanzee immune sera. To account for the distributions of the M-N--V-A-B-D types in man and in various apes, a genetic model is proposed that assumes the existence of two independent pairs of alleles: M/m, and N/n. In the processes of speciation, some of the alleles were lost or replaced by multiple mutations, resulting in chimpanzee in a series of codominant alleles responsible for as many as 16 M-N--V-A-B-D phenotypes.