The mtDNA haplogroup X2 has been found among Amerindians at extremely low rates (3%) and together with haplogroups A2, B2, C1 and D1 makes up the founding lineages of American Natives. The other haplogroups are found at higher levels A2 is roughly 51%, B2 at 18%, C1 is 19% and D1 roughly 6%. Clearly X2 is quite rare.
It is unsual for several reasons the main one is that unlike the others, there seems to be no basal population in Siberia or East Asia with X2 mtDNA. It is far more common in western Eurasia. Raising the question of how did it reach America and leave no treaces in Siberia or Beringia.
Back in 2014 I posted about it, at that time I wrote that "I was reluctant to engage in further investigations because I found the Solutrean hypothesis as a source for the X2 mtDNA population was rather weak, and some theories regarding ancient Greek admixture into the Cherokees and other North American natives as too flimsy (I omit the Mormon theories and quack Atlanteans as totally non-scientific). There were no serious papers on these subjects and mostly posts in questionable - racist - supremacist forums made me drop further research, until now.".
I suggested an early peopling of America by Neanderthals, overlaid by later Homo sapiens as an Eurasian source, via Beringia, for this X2 haplogroup, and discarded the Solutrean route across the Atlantic.
One year later, a paper published in 2015 by Raff and Bolnick (Does Mitochondrial Haplogroup X Indicate Ancient Trans-Atlantic Migration to the Americas? A Critical Re-Evaluation) looked into the matter and concluded that:
" We remain unconvinced by the arguments advanced thus far in favor of a trans-Atlantic migration prior to 1500 cal yr BP or so. As we have discussed, X2a has not been found anywhere in Eurasia, and phylogeography gives us no compelling reason to think it is more likely to come from Europe than from Siberia.
Furthermore, analysis of the complete genome of Kennewick Man, who belongs to the most basal lineage of X2a yet identified, gives no indication of recent European ancestry and moves the location of the deepest branch of X2a to the West Coast, consistent with X2a belonging to the same ancestral population as the other founder mitochondrial haplogroups. Nor have any high-resolution studies of genome-wide data from Native American populations yielded any evidence of Pleistocene European ancestry or trans-Atlantic gene flow."
The authors analyze the Solutrean (Europe to America via the Atlantic Ocean), and consider it improbable: "It is of course possible that genetic evidence of an ancient trans-Atlantic migration event simply has not been found yet. Should credible evidence of direct gene flow from an ancient Solutrean (or Middle Eastern) population be found within ancient Native American genomes, it would require the field to reassess the “Beringian only” model of prehistoric Native American migration. However, no such evidence has been found, and the Beringian migration model remains the best interpretation of the genetic, archaeological, and paleoclimate data to date."
Raff published another paper in 2017 and suggested a late arrival of X2a into eastern America and the Great Lakes region, where it now prevails, and defends the theory that it reached America through Beringia, once again mentioning Kennewick Man.
"The one exception to the absence of shared maternal lineages between the Maritime Archaic and Beothuk, X2a1/X2a1b, is interesting. Haplogroup X2a is found only in North America, primarily in populations around the Great Lakes, and the specific lineages present in the Maritime Archaic and Beothuk populations appear to be derived from the basal X2a lineage found in the 8,800 YBP individual from Washington State, known as Kennewick Man (or the Ancient One). This pattern may reflect the expansion of a population bearing X2a from the Pacific coast to the Northern Atlantic coast by about 4,000 YBP. Additional genomic analyses comparing Kennewick Man to the Maritime Archaic and Beothuk populations would provide a test of this model; if true, it would be a good step forward in understanding the crucial population movements following the Last Glacial Maximum that established regional patterns of genetic variation ."
I haven't found more recent papers, meaning that over the past 8 years, few scholars have looked into this matter. Only some DNA testing sites and Mormon groups have posted on X2 as you can see in the following examples:
- Native American Haplogroup X2a – Solutrean, Hebrew or Beringian?
- Your Haplogroup story: X2a
- A Mormon webpage (#1)
- Another Mormon webpage (#2)
From the Mormon page #2 is the following image, supporting a Trans-Atlantic route.
While preparing this post, I came across a post in Facebook which criticizes Raff and the Beringian entry route, instead it proposes a later Aleutian route: "The history of haplogroups X2a in North America is very clear. It came late, almost certainly in a single migration along the Aleutians, carried by a small group of founding women. Its initial spread was limited to the area of Washington and Oregon, after which is spread with the Algonquian expansion across the continent, beginning about 7,000 years ago. It was amplified in certain Algonquian groups, most clearly the Ojibwe, because of the early Algonquian practice of matrilocal cross-cousin marriage, which promoted the growth of communities that carried only a single mtDNA haplogroup."
Quite neat in my opinion. Asia is clearly the source of this haplogroup, I may disagree with the dates, but there is no way any "ancient" Europeans could have reached America by crossing the Atlantic Ocean. Beringia is an option too, along with an ancient entry. Was X2a overlaid by the A, B and C halpogrups the same way that D was?
Let's see what is uncovered by further research.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025 by Austin Whittall ©
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