Genetic Analysis of Indigenous Dogs from Siberia to Greenland: Implications for Interaction among their Human Companions
This project expands on a current study entitled "Genetic Analysis of Prehistoric Canis Remains from Across the North American Arctic: Implications for Interactions among their Human Companions (ARC-1108175)." Dogs and humans are intimately intertwined in the Arctic, and thus this project is contributing to anthropological and archaeological discussions concerning the movements and cultural interactions of indigenous peoples across the north. Because of large gaps in the human-DNA record, the original proposal not only investigates questions of the divergence of Asian and North American dogs but also investigates the possibility of using dog aDNA as a proxy for human movement in the Arctic. Ancient mitochondrial DNA from pre- and post-1000 AD dogs are compared to DNA from modern Inuit dogs (tested for independence from Eurasian stock post-contact) from across the Arctic. This project has already had broader impacts for Inuit identity, as the researhers have demonstrated that the Qimmiq or Inuit sled dog is the only indigenous breed remaining in North America (north of Mexico), and it accompanied ancestors of this region in their migration from Siberia to Greenland at least 800 years ago. Previous work on the original award to obtain archaeological bone and tooth samples from Alaska and Canada (North American Museum repositories) resulted in lower pre-1000 AD dog samples than anticipated (n=29; ca. 1/3 original estimate). Thus the PIs applied for additional support to enable travel to the Zoological Museum in Copenhagen, Denmark, to obtain additional pre-1000 AD samples from Alaska (three sites), Canada (one site) and Greenland (two sites). At the same time initially positive results and overwhelming enthusiasm from colleagues resulted in higher than anticipated post-1000 AD samples (n=400). With more than three times original estimate, the time to process these samples has increased; however, they are taking this opportunity to train additional graduate students in ancient DNA (aDNA). In addition, the expanded funding will support the use of a new aDNA sequencing routine known as next-generation that will provide much faster sequencing and allow for much higher resolution sequences. Training for this method will take place in Sweden, followed by dissemination of the method to researchers at UC Davis. The PIs hope that using more fined-grain analysis of modern and ancient samples using mitochondrial, Y-chromosome, STR and SNP markers, and autosomal microsatellites will allow them to "estimate the time of divergence between East Asian dogs and Arctic dogs," and determining whether these dogs diverged in Asia in the late Pleistocene or later during the later Holocene. Autosomal microsatellites may reflect enough variability to examine a proposed genetic bottleneck associated with an epidemic and/or potential culling Inuit dogs ca. 1950-1975. This study has already provided the first study of indigenous Inuit dogs, and now will produce an archaeological sample large enough to approximate a biological population. It will also underscore the importance of using human companions as a proxy for understanding prehistoric human movements and interactions.