Friday, January 11, 2013
Ojibwe and the X2a mtDNA Enigma
Kemp  identified 7 Jemes individuals from New Mexico,who shared X2a1a1 genes and who probably had an affinity with the Sioux/Cheyenne.With the exception of one Ojibwa sample all of the Hg X specimens analysed by U Perago  have the coding motif 8913-12397-14302.The anomalous Ojibwa did not cluster with any known X2a branches in North America or sister sub-clades in Eurasia.It "could" be another very rare founder.It has been designated assubgroup X2g.Private control region mutations distinguish two internal X2a branches ,which are X2a1 [143-16093] and X2a2 [225-16254C].X2a1 tends to be concentrated in the Great Lakes and Great Plains region X2a2 is less common [X2a1,19; X2a2,3; X2/,1].Some western fringe X2a specimens [eg:Nuu-Chah-Nuth,Yakima] lack characteristic X2a1 and X2a2 mutations [Ibid].
The current North American distribution of X2a tends to be concentrated in the vicinity of the Great Lakes/Great Plains with frequencies as high as 25% among some Algonquian people [eg:Ojibwa] with diminishing clines to the west and south.Frequency estimates range from Sioux ca 15%,Nuu-Chah-Nuth ca 13.5%,Navajo ca 6.5%,and Yakuma ca 4.8% [M Brown,1998].There are a few single or very frequency occurrences of X2a lineages distal to the "Ojibwa core".One X2a individual was identified among the Shuswap in the Caribou country of British Columbia and 5 0f 63 [7.9%] Nuu-Chah-Nuth samples off the west coast of British Columbia are probably X2a [there is not sufficient definitive data to substantiate this premise].The above tend to support the theory that X2a was introduced to North America from NE Siberia and that a number of intermediate Hg X lineages have been lost.A Nonosabasat sample from Newfoundland,eastern Canada,had X2a[10693C,16189C, 16213A,16223T,!6278T].A number of single occurrences have been reported from the Gaspe Peninsula,Quebec Province,but the data has not been sighted.G Horvati  stated that X2a was identified in 3 of 6 MicMac sequences.
The dearth of indigenous mtDNA samples from the Maritime Provines of Canada,Quebec and British Columbia severely detract from endeavours to reconstruct the migration paths of the initial X2a colonists to North America.Consequently there has been a significant degree of speculation about the entry point to North America and the coalescence dates of X2a.Its apparent,current concentration in the Great Lakes/Great Plains region is an anomaly,which can not be confidently reconciled with an Alaskan entry point.This genetic founding lineage was probably introduced to North America from NE Siberia after the glacial era,but the current dispersal pattern of X2a is not in total accord with this supposition."If" the Ojibwa did move from Nova Scotia to the Great Lakes region ca 1400 ADE,the enigma gains in complexity.
M Kujanova  identified three subgroup X2j specimens in North Africa.V Fernandes  noted that X2j shared a mutation at position 12397 with the North American subgroup X2a.She cautioned that the mutation could be a recurrence and that X2j appears to have evolved recently.The rare North American X2g lineage is compatible with the spread of of Hg X from the Near East towards the New Morld as early as the emergence of the X2+225 clade [ibid]. - More ...
Posted by shvt at 5:29 PM