Ancient DNA from the Ohio Hopewell
Amazing results of a study of ancient DNA from the Hopewell site! Lisa A. Mills conducted a study of ancient DNA recovered from human remains from mounds at the Hopewell site, Ross County, Ohio. The results of her work are presented in her doctoral dissertation: Mitochondrial DNA analysis of the Ohio Hopewell of the Hopewell Mound Group. PhD Dissertation by Lisa A. Mills, Department of Anthropology, Ohio State University, 2003.
The Hopewell Mound Group is located in Ross County along the North Fork of Paint Creek, about four miles northwest of Chillicothe. It is part of the Hopewell Culture National Historical Park [http://www.nps.gov/hocu/]. The Hopewell culture [http://www.ohiohistorycentral.org/entry.php?rec=1283] extended across much of eastern North America, but its heartland was here in central and southern Ohio. Hopewell culture sites range in age from 100 BC to around AD 500. For more about the Hopewell culture, see http://www.heathohio.org/about/hopewell.html.
Mills successfully extracted mitochondrial DNA (mtDNA) from the teeth of 34 individuals originally excavated by H. C. Shetrone who was, at the time, Curator of Archaeology for the Ohio Archaeological and Historical Society (now called the Ohio Historical Society). These human remains were excavated from mounds of the Hopewell Mound Group between 1922 and 1925 and subsequently have been curated by the Ohio Historical Society. Mills sampled a total of 49 individuals so her success rate at recovering DNA was 69%. This rate of success indicates excellent preservation of DNA. Although based on a relatively small sample of individuals, the results are promising and provocative.
First, Mills noted that the people she studied from the Hopewell site represented a very diverse group. The sample included 4 out of the 5 documented Native American lineages (haplotypes) [see http://www.centerfirstamericans.com/mt.php?a=203 and http://en.wikipedia.org/wiki/Haplogroup_X_(mtDNA) for more information about Native American DNA]. This apparent diversity might suggest that individuals from different groups were buried together in these mounds.
Second, comparisons between the mtDNA from individuals from the Hopewell site and a database of mtDNA from groups from all over the world, demonstrated that these ancient Native Americans shared close ties with Asia especially, China, Korea, Japan, and Mongolia. This offers strong support for the already well-supported conclusion that Native Americans originated in Asia and migrated to the Americas in the past 15,000 years.
Third, comparisons between the mtDNA from these individuals from the Hopewell site and a database of mtDNA samples from 50 ancient and modern Native American groups provided evidence of some biological relationships. There were clear links between these people and individuals from two Adena culture [http://www.ohiohistorycentral.org/entry.php?rec=1287] sites as well as individuals from the even earlier Glacial Kame culture [http://www.ohiohistorycentral.org/entry.php?rec=2049]. This confirms the inference that the people of the Hopewell culture were the descendants of people of the Adena culture (circa 800 BC to AD 1) who were, in turn, descended from the local Archaic cultures (circa 3000-500 BC).
Interestingly, however, the Hopewell site individuals did not show a close relationship to the Fort Ancient culture samples [http://www.ohiohistorycentral.org/entry.php?rec=1285]. Perhaps, as some scholars have suggested, some Fort Ancient-era groups (circa AD 1000-1650) moved into Ohio from elsewhere. The most closely related ancient groups outside of Ohio included individuals buried at the 700-year-old Norris Farm mound in central Illinois. Also, Mills found that one particular female buried at Mound 25 at the Hopewell site had a rare mutation that she shared with several elite individuals buried at the 1000-year-old Cahokia site [http://www.cahokiamounds.com/cahokia.html].
Modern groups with whom the individuals at the Hopewell site shared some degree of relatedness include the Chippewa/Ojibwa [http://www.ohiohistorycentral.org/entry.php?rec=2090] and Kickapoo of the Great Lakes region. Some genetic links also are indicated between one or more of the individuals from the Hopewell site and tribes as diverse and widespread as the Apache, Iowa, Micmac, Pawnee, Pima, Seri, Southwest Sioux, and Yakima. Mills looked, in particular, for evidence of ancestral ties between the individuals at the Hopewell site and Cherokee Indians, since some oral traditions have suggested a relationship between them. She found that Cherokee mtDNA samples do not cluster close to the Ohio Hopewell.
Finally, Mills found that multiple burials at the Hopewell site included individuals with different mtDNA profiles, indicating they did not share a recent female ancestor (since mtDNA is passed from mother to child). This further indicates that the people at this Hopewell culture site did not base their burial practices on principles of matrilineal descent. Due to the small sample size, the conclusions are tentative.
Mills work, however, confirms that DNA is recoverable from 2,000-year-old bones and that it can be used to make inferences about biological relationships between and among ancient populations and their descendants. It also demonstrates the importance of museum collections, including ancient human remains.