MOLECULAR-GENETIC CHARACTERISTICS OF THE NEOLITHIC POPULATION OF THE BAIKAL REGION - RFLP OF THE ANCIENT MTDNA FROM OSSEOUS REMAINS FOUND IN THE UST-IDA-I BURIAL GROUND

Nineteen mtDNA samples from osseous remains found in the Ust-Ida I bur ial ground (middle Angara River) were analyzed. An ancient population dated back to 4020-3210 B.C. by radiocarbon (C-14) analysis and archeo logically assigned to the Neolithic Isakovo culture of the Baikal regi on was described in terms of molecular genetics. Data on restriction-s ite polymorphisms in fragment 16 106-16 545 of the mtDNA D-loop were o btained for seven restriction endonucleases. On the basis of these dat a, the mitotypic structure and nucleotide diversity of the ancient pop ulation were determined. The molecular genetic characteristics of the Neolithic population were compared to the modem populations of Siberia , Mongolia, and Urals. The data obtained indicate that the studied Bai kal Neolithic population was ancestral for the modem indigenous Siberi an population. The time of divergence of the three regional population s (5572 years ago) was estimated from the genetic distances between th e Neolithic and modem Siberian populations, assuming that the average rate of nucleotide substitution was constant. This estimation agrees w ith the results of the radiocarbon dating (5542-5652 years ago). The f act that the studied samples were C-14-dated allowed the rate of nucle otide substitution in the studied region of mtDNA D-loop to be directl y determined.