[Detection of the adaptive significance of human blood group polymorphism by analyzing a series of loci. Level of heterozygosity and variety of phenotypes in two generations].

Phenotypes of the blood group systems AB0, Rhesus, MNSs, and P are determined, 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. Mothers are shown to differ from their offspring by higher average heterozygosity, lower phenotypic diversity, and a reduced frequency of the "rare" interlocus phenotypic combinations. An optimal heterozygosity level, which provides maximum fitness for a large class of genotypes, is revealed in the reproductive part of the population, while the average population heterozygosity level is two-thirds of the optimal level.