Russian Old Believers: Genetic consequences of their isolation, as shown by mitochondrial DNA evidence

The objective of this dissertation was to test the hypothesis that populations of Russian Old Believers, persecuted by the Russian Orthodox Church and exiled to Siberia between 200 and 300 years ago, have genetically diverged from other Slavic populations as a result of their isolation. Measures of genetic diversity were obtained by surveying maternally inherited mitochondrial DNA (mtDNA) for informative variable nucleotide sites in the coding region and control region, using restriction fragment length polymorphism and direct sequencing methods. The sample included 189 unrelated Russian Old Believer individuals from three populations in Siberia: Burnyi in the Baikitsk Raion of the Krasnoyarsk Krai, and Isetsk and Kirsanovo in the Tyumen Oblast. mtDNA variation was also analyzed in 201 ethnic Russians from different parts of Siberia to determine the genetic relationship between Old Believers and other Slavic groups. Statistical analyses included mtDNA data from other comparative Slavic populations available in previously published literature.; The mtDNA data generated from this project were used to address three major questions about the Old Believers: (1) Have the Old Believers living in isolation in Siberia for 350 significantly diverged from other Slavic populations? (2) If no significant divergence is found, are there any signs of mtDNA differentiation between the Old Believers and other Slavic populations? And, (3) do the three Old Believer populations analyzed in the present study represent one mtDNA gene pool?; My results indicate that the Old Believers have not significantly diverged from other Slavic populations over the 350 years of their isolation in Siberia. However, they show some unique patterns of mtDNA variation relative to other Slavic groups, such as a high frequency of mtDNA subhaplogroup U4, a surprisingly low occurrence of haplogroup H, and the appearance of rare East Eurasian subhaplogroup D5 sequences. Although the Old Believers show no significant evidence of genetic constriction, these distinctive patterns are discussed as possible signs of founder effects.