A GENETIC AND DEMOGRAPHIC-STUDY OF DAGHES TAN HIGHLAND POPULATIONS AND MIGRANTS FROM THEM TO LOWLANDS - STUDY ON GENETIC AND MARRIAGE STRUCTURES

The results of a genetic and demographic study of two ''split'' isolat es of small native ethnic groups of Daghestan are described. Parts of these populations were resettled from habitual highland ecological con ditions to radically new lowland conditions in the 1940s. These split isolates were compared with a population of native inhabitants of the Daghestan lowland. It was found that, since resettling, separated popu lations originating from split isolates became significantly different in both marriage and genetic structures. This is manifested in differ ent phenotypic and allelic frequencies of a number of physiological an d biochemical markers and in levels of their heterozygosity. To explai n the differences revealed, a hypothesis was proposed about the relati onship between levels of inbreeding, heterozygosity, and physiologic s ensitivity that account for the differential adaptability of members o f the isolated populations to changing environmental conditions. This is the first report of a series of papers describing the experimental testing of this hypothesis. While testing the validity of the hypothes is in this study, a positive linear correlation was found between inbr eeding and homozygosity levels.