EVALUATION OF ADAPTIVE SIGNIFICANCE OF HU MAN BLOOD-GROUP POLYMORPHISM BY ANALYSIS OF A SET OF LOCI

Phenotypes of the blood group systems ABO, Rhesus, MNSs, and P are det ermined, and the levels of individual heterozygosity are estimated for a set of loci studied in representative samples of newborns and their mothers, representing two generations of the Moscow population. Mothe rs are shown to differ from their offspring by higher average heterozy gosity, lower phenotypic diversity, and a reduced frequency of the ''r are'' interlocus phenotypic combinations. An optimal heterozygosity le vel, which provides maximum fitness for a large class of genotypes, is revealed in the reproductive part of the population, while the averag e population heterozygosity level is two-thirds of the optimal level.