Date of Award

4-30-2011

Degree Type

Thesis

Degree Name

Cell and Molecular Biology (M.S.)

Department

Cell and Molecular Biology

First Advisor

Alex Nikitin, Ph.D.

Second Advisor

Agnieszka Szarecka, Ph.D.

Third Advisor

Rod Morgan, Ph.D.

Abstract

Studies of mitochondrial DNA (mtDNA) polymorphism have provided valuable insights for understanding patterns of human migration and interaction. The ability to recover ancient mtDNA sequence data from post-mortem bone and tissue samples allows us to view snapshots of historic gene pools firsthand, provided that great care is taken to prevent sample contamination. In this study, we analyzed the DNA sequence of the first hypervariable segment (HVSI) of the mtDNA control region, as well as a portion of the coding region, in 14 individuals from three collective burials from the Neolithic Dnieper-Donetz culture and three individuals from Bronze Age Kurgan burials, all located in modern-day Ukraine on the northern shores of the Black Sea (the North Pontic Region, or NPR). While most of our samples possessed mtDNA haplotypes that can be linked to European and Near Eastern populations, three Neolithic and all three Bronze Age individuals belonged to mtDNA haplogroup C, which is common in East Eurasian, particularly South Siberian, populations but exceedingly rare in Europe. Phylogeographic network analysis revealed that our samples are located at or near the ancestral node for haplogroup C and that derived lineages branching from the Neolithic samples were present in Bronze Age Kurgans. In light of the numerous examples of mtDNA admixture that can be found in both Europe and Siberia, it appears that the NPR and South Siberia are located at opposite ends of a genetic continuum established at some point prior to the Neolithic. This migration corridor may have been established during the Last Glacial Maximum due to extensive glaciation in northern Eurasia and a consequent aridization of western Asia. This implies the demographic history for the European gene pool is more complex than previously considered and also has significant implications regarding the origin of Kurgan populations.