[Ecologically conditioned changes in gene frequencies for polymorphic systems in the nonnative population of the northeastern USSR].

Examination of 1051 healthy residents of Magadan in terms of nine polymorphic systems has shown changes in phenotype frequencies depending on duration of the persons' staying in the North. The frequency pattern of phenotypes is significantly different among men and women. The phenotype frequencies of alkaline serum phosphatase and acidic erythrocyte phosphatase were found in a more strict correlation with the northern residence term. The part played by selective migratory behaviour in development of genetic structure of population is discussed and also possible ecologic factors resulting in phenotype and gene frequency changes are analysed.