Restriction polymorphism of the major noncoding region of mtDNA in the indigenous population of Tuva

Mitochondrial DNA sequence variation was examined in three rural population s of the indigenous inhabitants of the Tuva Republic. The frequencies of re striction sites within the D-loop region of mtDNA were determined. The thre e populations studied demonstrated similar patterns of mtDNA polymorphism. Like other Siberian populations, Tuvinians were characterized by high frequ encies of the Haem 16517 and AspS9I (Cfr13I) 16516 restriction sites (about 75%). Moreover, in Tuvinians, a relatively low (71 to 81%) frequency of th e KpnI 16129 restriction site was observed. The frequency of the mitotype d iffering from the Cambridge sequence by the HaeIII 16517 and KpnI 16129 sit es in Tuvinians was higher than in Mongols and Russians. The features of mt DNA polymorphism point to the similarity between Tuvinians and other Siberi an ethnic groups (Sel'kups in particular). This can be explained by the con tribution of the Samoyed component, dong with the Turkic and Mongoloid ones , to the formation of the Tuvinian ethnic group.