I.N. Medvedev, I.V. Amelina

The method of selective silverung of the chromosomes' kernal forming areas (KFA), worked out in the 70s , made it possible to study the transcriptional activity of these regions on the cytologic level, by which a new type of human chromosomes polymorphism  Ag polymorphism  was brought to life. The work with genetic markers having broad populational polymorphism is supposed to be very promising in populational genetic investigations. The ability of acid proteins of KFA to be silvered  Ag activity  is one of such markers. In lite-rature some information on the study of populational Ag-polymorphism is available, but the works on the correlation between the KFA activity and phenotypic pecularities of people in the conditions of isolation by distans are lacking. The aim of this research is the study of the regularity of the phenotypic manifestation of the KFA transcriptional activity on the populational level through the evidence of isolation by distance. During the investigation of the populational characteristics of Ag-polymorphism of the natives of the Kursk region the increase of the transcriptional activity of chromosomes' KFA in the condi-tions of isolation by distance has been exposed, which is reflected in the negligible presence of Ag KFA with 0 c.u. Among the natives of the Kursk region the functional Ag-polymorphism is within normal range. In the conditions of isolation by distance the Ag-polymorphism pecularities were re-flected in the prevalence of KFA with 1 c.u.in Group D chromosomes, and in the prevalence of KFA with 3 c.u. - in Group G chromosomes. The accumulation of KFA with large Ag-blocks (4 c.u.) may take place in extremely unfavorable conditions, but Kursk region is not a attributed to such regions, which explains the fact of low amount of KFA with 4 c.u. in its population. The comparative analysis of the groups of volunteers in the amount of 10 Ag KFA demon-strated a high rate of differences between the investigated data on isolation by distance. With the increase of the amount of 10AgKFA the distance between the places of birth of the ancestors of two generations decreases. On isolation by distance dominant allels were accumulated in the population, which led to the increase in the amount of 10AgKFA in individuals, explaining the shortest distances between the places of birth of the closest relatives with high amount of 10AgKFA. At the same time, the registration of the small amount of 10Ag KFA in a person under investigation exposed a large dis-tance between the places of birth of his two generations of ancestors. The found regularities were not influenced by dividing the respondents into males and females. Thus, isolation by distance influences considerably the Ag-polymorphism of the natives of the Kursk region, providing them with the system of adaptation to the unfavorable environmental fac-tors.