Distribution of mitochondrial DNA lineages among Native American tribes of Northeastern North America

Abstract The mtDNA haplogroups of 185 individuals from Native American tribes in Northeast North America were determined. A subset of these individuals was analyzed by sequencing hypervariable segments I and II of the control region. The haplogroup frequency distributions of populations in the Northeast exhibit regional continuity that predates European contact. A large amount of gene flow has occurred between Siouan-- and Algonquian-speaking groups, probably due to an Algonquian intrusion into the Northeast. The data also support both the Macro-Siouan hypothesis and a relatively recent intrusion of Northern Iroquoians into the Northeast. These conclusions are consistent with archaeological and linguistic evidence.

The Northeast culture area of North America (Driver and Massey 1957) extends from the western end of the Great Lakes to Maine. The principal language families in this area include Iroquoian in the east, Siouan in the west, and Algonquian throughout the entire region (Campbell and Mithun 1979; Campbell 1997). The distribution of these language families within and beyond the Northeast, together with the archaeological record, have fostered hypotheses about large population movements and admixture during prehistoric times (Siebert 1967; Lounsbury 1978). For example, Goddard (1994) demonstrated a west-to-east cline in declining depth of common ancestry among Algonquian languages, and this may be interpreted as evidence that Algonquians migrated eastward from a homeland in the west. The Red Ocher/ Glacial Kame twin burial complex (2500-2000 ybp) in the southern Great Lakes Region might be the cultural manifestation of these recently arrived proto-Algonquian-speaking people in the east, who are hypothesized (by Denny 1991) to be descendants of the people of the Western Idaho Archaic Burial Complex located on the Columbia Plateau, between 4000 and 1000 years earlier (Pavesic 1985). Fiedel (1987) argued that the Point Peninsula culture (2200-1300 ybp) is the material manifestation of the further spread of Algonquian-speaking ancestors into the northern Great Lakes Region from southern Ontario. The replacement of dolicocephalic Otamid populations by brachycephalic Lenapid populations of the Great Lakes and Ohio Valley regions constitutes craniometric evidence for an intruding population into the Great Lakes region from the Pacific Northwest (Neumann 1952). The appearance of the Red Ocher/Glacial Kame Burial complex in the Great Lakes Region coincides with the estimated time, based on glottochronological evidence that proto-Algonquian began to diversify into its Algonquian-- speaking descendants (Denny 1991). However, that there is a link between the Western Idaho Archaic Burial Complex and a proto-Algonquain population is not widely accepted among North American prehistorians.

Siouan groups that were pushed into the Plains by the expansion of Algonquian groups are closely related linguistically to groups (e.g., Biloxi, Catawba, Ofo, Tutelo) that lived in the Southeast United States at contact (Campbell and Mithun 1979; Campbell 1997). Chafe (1976) has proposed the existence of a Macro-Siouan language stock consisting of the Iroquoian, Siouan, and Caddoan language families, which might have originated in the Southeast. Populations from all three of these groups are now widely scattered throughout the Northeast, Plains, and Southeast regions.

Northern Iroquoians constitute another hypothesized immigrant population in the Northeast. During the past few decades archaeologists have used an in situ model of development for explaining culture change in the Northern Iroquoian region (Lounsbury 1978). Recently, however, Snow (1995) reiterated the idea of an Iroquoian intrusion and presented evidence of an Iroquoian migration into the Northeast from the southeastern United States, where other Iroquoian groups, such as the Cherokee, lived during the early historic period. Snow (1995) argued that there is a clear discontinuity in the archaeological record resulting from the intrusion of Iroquoian-speaking people into Algonquian territory approximately 1200 ybp. Such population movements, and any resulting admixture, should cause detectable patterns in the mitochondrial DNA (mtDNA) diversity in populations of this region.

All unadmixed modern Native Americans are members of one of five different maternal haplogroups: A, B, C, D, or X. Each haplogroup is defined by a restriction site gain or loss or by the presence of a 9 base-pair (bp) deletion, as well as by corresponding point mutations in the control region (CR) of mtDNA (Schurr et al. 1990; Torroni et al. 1993; Forster et al. 1996; Brown et al. 1998). The frequency distributions of these five haplogroups differ significantly among Native American groups in North America (Lorenz and Smith 1996; Smith et al. 1999). For example, haplogroup A is high in frequency in Native American populations in the northern region of North America (occupied mainly by Athapaskan and Eskimo/Aleut speakers). It is, however, nearly absent in Native American populations of the Southwest United States (except in the Navaho and Apache, Southern Athapaskan speakers who are relatively recent emigrants from the North), where haplogroup B predominates. In at least some geographic regions this patterning of haplogroup distributions in North America appears to have prehistoric continuity as well. For example, data from ancient populations in the Southwest United States indicate that haplogroup B has been the most common haplogroup in the region at least as early as 3000 ybp (O'Rourke et al. 2000).