My previous post looked into the three theories that explain how the Y chromosome Q hg, with a clearly non-European origin, managed to get into the heart of Europe from its supposedly
archaic homeland in Central Asia. We saw how the Huns, Cimbrians and Mongols may have been the human vectors bearing this haplogroup in their "Asian" Y-Chromosomes and carrying it with
their invasions into the heart of Europe.
But, could there be another explanation for the presence of Q hg in Europe? To be able to address the issue, we have to look at the facts and the haplotypes of current and past Europeans. Today's post will do just that.
The Ancient Dispersal theory
As an alternative to the alleged historical dispersal that supposedly took place between 103 BCE and 1245 CE, it is probable that the Q haplogroup is actually very ancient and spread across Europe long before the Huns, Mongols or Cimmerians appeared on its eastern borders.
In fact, the genetic imprint of the repeated invasions of Asian nomads on the Y chromosome haplogroups in Moldavia, on the main route used by most of these hordes, was minimum which is in ".. good agreement with earlier studies on Y-chromosome variation in eastern and central Europe, asserting a minimal impact of gene flow from Siberia/central Asia". [1]
The European genetic data shows that Q hg found at very low frequencies: between 0.2 and 2% in most of Europe (except a few hot spots with higher frequencies). This may show the ghost outline of a population that once occuped a vast swath of Europe, but was later replaced and watered down, to its current low frequencies by other Y chromosome haplogroups during the Neolithic (as happened to I haplogroup during that same period [2]). And, once again I am thinking of our Neanderthal predecesors, who lived in this region and were replaced by modern humans (more on this below).
In other words, what we currently see are the relicts of an archaic dispersal of haplogroup Q.
Since haplogroup Q branches off from P hg much earlier than the R hg that nowadays prevails in most of Europe, it would be a reasonable assumption to find Q underlying R in the European continent, that is: widely spread out, but at lower frequencies as successive migrations incorporated other haplogroups into the continent with varying success rates in their new habitats.
In fact, Paleolithic migrants introduced R (xR1a) -the x stands for "excluding"- haplogroup into Europe from the East, and it is the most frequent (37%) haplogroup on the continent, mainly in its Western regions. The other high-frequency haplogroups are E2b (which came from the south), J (from the Southeast) with the introduction of farming, and N, among the Uralic speakers (Northeast). [3]
Could they have spread over an earlier European population?, one with hg Q? Do we even have evidence of an archaic hg Q presence in Europe? Let's see what the sequencing of ancient Europeans tells us:
The Motala remains
The remains of several persons were found at the Kanaljorden site at Motala in Central Sweden in 2009. They were deposited in a small lake, during rituals which included displaying skulls on stakes and placing human bones inside skulls. They have been dated to between 6,212 and 5,675 Cal BC, making them about eight thousand years old.
Recently the genes of six of the Motala remains were sequenced, and the Y-chromosomes of all but one of them, were classifeid as belonging to I hg; the remaining one was probably a Q1a2 hg.
This is remarkable since, as seen above, today hg I is not found at high frequencies among Europeans; yet it was prevalent among Mesolithic hunter-gatherers. This "suggest[s] an old origin" [2]. (Currently it is found in Sardinia, North Germany, Moldavia, Scandinavia and the Western Balkans, probably due to recent expansions and not to archaic settlements).
The Q element in Motala
So we have a doubtful Q1a2 haplotype found in Motala [6]; why is it questioned?
The doubts surrounding the haplogroup of Motala [6] are due to the fact that it carried the marker L55, that is: L55+ (19413335 G>A). This marker is only found in Y-haplogroup Q's haplotype Q1a2a (and branches that arise from it) and in no other haplogroup. But... and this is perplexing, it is L232 -, that is, it does not carry marker L232 which is necessary to make it part of haplogroup Q1.
These are phylogenetically inconsistent findings and the authors of the paper that describe the remains state, quite reasonably, that they "are unable to assign a haplogroup to this individual [2].
A review of all global haplotypes listed at the website www.semargl.me [4], does not show one single person with a L232- marker (that is, lacking it but belonging to Q hg). So it is either very rare or, it is not tested for unless the individual is known to belong to the Q hg, in which case it is then tested for to define the haplotype.
Afontova Gora 2
Genetic tests were also done on remains uncovered at the Afontova Gora 2 site in Siberia, within the city of Krasnoiarsk on the banks of the Yenisei River (56° N 92&deG;51' W). These are also old (17 kya) human remains, and inital information on it indicated that it was Q1a1 [5][6]; these were later retracted and it was classified as R1 (perhaps due to contamination during handling).
If confirmed as carriers of Q hg, both men could point at hunter-gatherers belonging to minor lineages such as Q1a and its downstream branches in both Europe [7] and Siberia between 17 and 8 kya.
Amerindians in this context
Motala [6] if Q1a2 and Afontova Gora 2, if Q1a1, would both be closer to the root of the Q hg tree, more basal, than the Amerindians (with M3 marker) and other Scandinavians (L804 lineage). Meaning that they split earlier from the branch that later led to contemporary Scandinavians and American Natives.
The data on most of the Scandinavians (which lacks detail in many cases regarding haplotype markers) places them downstream from Q1a2 (further away from the root) together with some Siberian groups. Even further away from the root we find the Native Americans with M3 and a specific haplotype found in Scandinavians (those carrying L804, L807). [8][9][20] See the tree below.
Since the split originating the two haplotypes found in America: L54 (Q1a2a1) and M3 (Q1a2a1a1) has been dated to roughly 22 kya (see my previous post), then these other European haplotypes from Motala and Krasnoiarsk, which are closer to the root should then be much older than 22 kya. (and therefore older than the remains that have been sampled - 17 and 8 kya). This pushes far back in time, to a period contemporary with Neanderthals in Eurasia.
Link between Scandinavia and America
So we have two populations, one in America and another in Scandinavia which derive from a common root, Q1a2a1a, and which are separated by thousands of kilometers of "Siberia"; this suggests that they share a common origin in Siberia [10] and that they each moved on from this source into the areas where we now find them.
Since an earlier (closer to the root) split (L54) is also found in America, we could suppose that it reached the New World first, however (see my previous post) these L54 derived haplotypes are actually younger than the M3 ones!
Then we have the more basal Scandinavians, closer to the root, whose haplotypes are closer to those found in India, Pakistan and the Middle East (Q1a2*) as well as Afghanistan, Central Asia, Russia, Georgia and Germany (Q1a2b). These haplotypes have been dated as being only 2,200 - 2,150 years old, [11], far too young in my opinion and which clearly do not fit the tree! (perhaps the dates were adjusted so they could justify the Cimbrian theory -see my last post.
So, leaving the dates alone for the time being, let's follow the mutational trail: a mutation once acquired should not be lost, but as we have seen, Motala [6] has the L55 mutation of Q1a2a, which would place it at the same level as the two mutations mentioned in the previous paragraph (Q1a2 and Q1a2b), making it older than the other Scandinavian and Amerindian haplotypes mentioned further up (M3 and L804).
But it lacks the M232 mutation which is found in all Q haplogroup members. Why? Was it lost in a back mutation?
Probably: although back mutations (or reversions) are not common, they are known to happen [12], for instance in marker P25 which has mutated at least twice [13]. Are other markers similary unstable? Most likely. A reversion would explain why the M232 marker is absent in Motala [6] and place him in the Q1a2a hg. See tree below:
Dispersal
We know, as per mainstream orthodox theories, that the Q haplogroup first appeared in South Central Siberia (yellow star on map below) where it sprung from P hg. It then spread (red arrows) east and west (the pink regions are the current areas where it is found in high frequencies); it also spread southeast and southwest into India and the Middle East. Those going towards America took a northern route, close to the retreating glaciers, perhaps enticed by the good hunting grounds of the Siberian tundra.
In this context then, we can envisage a split in the ancestral Q1a2a1 hg group, into two populations:
- The future Scandianvian Q1a2a2 with the L804 mutation
- The future Amerindian Q1a2a1 with the M3 mutation only found in America (and some Bering Asian natives - result of a back-migration from America into Asia).
This ancestral lineage Q(xM3) -the x stands for excluding- is found among the Khakass people in Siberia, south of Krasnoyarsk, with an average frequency of 4.8% (with maxima of 28% among the Butrakthy Sagais), clearly indicating that Q hg "is the most ancient one in Siberia... mark[ing] the Paleolithic human migration along the Boreal pathway... constitut[ing] a major part of the chromosome Y pool of the first migrants to Siberia in the early stages of human expansion to North Eastern Asia." [14]
Its eastern range extended into Europe, where it is found at relativley low frequencies:
Current frequencies of Q haplogroup in Europe
Notice that some studies yield 0% frequency while others show a higher rate (i.e. among Icelandic and Khantys), perhaps due to sampling bias. Also, some studies have not dug deeper into the different haplotypes so there are many blanks in the data:
- 0.0% Serbian, Croatia, Bosnia, Kosovo, Albania, Macedonia, [5] Greece, Bosnia -Croats, Bosnia-Serbs, Slovenia, northeast Italy, Hungary, Czech Republic, Poland, Georgia and Balkaria [15] Ireland, [16], Russia (Eastern European part - Arkhangelski, Kursk, Tver, Izhemski Komi, and Priluzski Komi) [17]
- 6.10% Hvar Island, Croatia (Q*-M242) [18]
- 0.71% Herzegovina. [5] (mentioned as Q-M242 only)
- 1.10 % Ukraine (Q M242) [15]
- 0.80% Moldavia (Q M242) [1]
- 0.10 - 1.60% Bulgaria Depending on the region: 0.1% Q-M25 and Q-M346; 0.2% Q-M378. Peaks of 1.6% and 1.3% Q-M378, in Lovech and Montana on the south shores of Danube River [19]
- 0 - 3.70% Russia, Siberia (Khanty) (Q1a2...) [17][21]
- 3.00% Faroe Islands [16] Matching Norweigan haplotypes
- 2.00% Norway [16]
- 0 - 7.00% Iceland [16][22]
- 3.00% Sweden [16], but has regions with higher frequencies -up to 22.2%- (See the map [9]
- Denmark, Haplotype distribution: [9]
- 10% Q1a2b
- 8% Q1a2*
- 8% Q1a2a1a2 (with L804 - 807)
- 60% Q1a2 60% (unspecified haplotype)
- 0.08% Sardinia (Q1a3c) [8]
The Amerindian link revisited
We tend to imagine Q haplogroup moving towards the West, into Scandinavia and from there, dispersed widely by the Vikings to the Faroe Islands and Iceland. But could it have reached Iceland and Europe from the West? That is, from America, and spread East?
The Icelandic sagas of the Vikings mention the hostile encounters between the Norse and the "Skraelings" (Native Americans), making it unlikely that they mixed. However, in the Greenland colony the ancestors of the Innuit (Thule people) may have wed widowed Viking women, incorporating their Q hg into the local population which later reached the Scandinavian mainland and Iceland after their return in the XVth century when they abandoned Greenland.
We would have to screen Innuit for the Q haplotypes found among Scandinavians to answer this. It is a possible explanation. Perhaps it is even older than the Vikings, and reflects the admixture of small party of archaic Innuit paddling across the fringes of the Arctic ice cap and reaching Scandinavia, where they mixed with the locals. But this would be unlikely due to the small size of the kayaking Innuits in comparison to the locals and would have minimized the impact of their Y chromosome in the Scandinavian population.
By the way, there is also a circumpolar C1 mtDNA haplogroup prevalence, one that links America (where it is found at very high frequencies), Siberia, Iceland and Northwestern Eurasia... which may be tied to the archaic Innuit Y chromosomes, or may indicate that those who carried them, once lived in this area surrounding the Arctic, but prevailed in the Americas.
The Neanderthal link
But, going full circle and returning to my opening comments, after looking at the map above I keep on thinking that there must be some link between Neanderthals and haplogroup Q.
The map is shaded with a yellow color in the territory once occupied by the Neanderthal at the time modern humans began their supposed Out Of Africa migration. The Altai source for hg Q in one of Neanderthal's known sites, is intriguing.
It would also explain its presence at low frequencies in Europe, its predominance in America, where Native Americans carry a high proportion of Neanderthal ancestry, and account for its very old age and wide range across Eurasia, underlying more recent "modern human" lineages. It may also account for the mtDNA C1 haplogroup found in the same regions.
But this will be the subject of another post.
Sources
[1] Varzari A, Kharkov V, Nikitin AG, Raicu F, Simonova K, et al. ,(2013). Paleo-Balkan and Slavic Contributions to the Genetic Pool of Moldavians: Insights from the Y Chromosome. PLoS ONE 8(1): e53731. doi:10.1371/journal.pone.0053731
[2] Lazaridis, I. et al. (2013), Ancient human genomes suggest three ancestral populations for Europeans. biorxiv.org, pre-print online 23 December 2013.
[3] Mark Jobling and Chris Tyler-Smith., (2003) The Human Y chromosome an evolutionary marker comes of age. Vol 4. Aug. 2003, p598 www.nature.com/reviews/genetics
[4] www.semargl.me
[5] Y-SNP calls for Afontova Gora 2. Genetiker. May 2014
[6] Source: See first column under AF2
[7] Europedia. Geographic spread and ethnic origins of European haplogroups.
[8] Paolo Francalacci et al., (2013). Low-Pass DNA Sequencing of 1200 Sardinians Reconstructs European Y-Chromosome Phylogeny. Science 341, 565, DOI: 10.1126/science.1237947
[9] Svenska Haplogruppdatabasen
[10] Danish Demes, A Regional DNA Project for Danish Americans and Danes around the World
[11] I. Rozhansky, (2010). Riddle of the Cimbri. Experience the historical and genealogical investigation. Proceedings of the Russian Academy of DNA Genaology, v.3., p. 545 (Russian language)
[12] Jennifer F. Hughes and Steve Rozen, (2012). Genomics and Genetics of Human and Primate Y Chromosomes. Annu. Rev. Genom. Human Genet. 2012.13:83-108. 10.1146/annurev-genom-090711-163855
[13] Adams SM, King TE, Bosch E, Jobling MA., (2006). The case of the unreliable SNP: recurrent back-mutation of Y-chromosomal marker P25 through gene conversion. Forensic Sci Int. 2006 May 25;159(1):14-20. Epub 2005 Jul 18.
[14] V.N. Khar’kov et al., (2011). Genetic Diversity of the Khakass Gene Pool: Subethnic Differentiation and the Structure of Y Chromosome Haplogroups. Molekulyarnaya Biologiya, 2011, Vol. 45, No. 3, pp. 446–458.
[15] Battaglia V, Fornarino S, Al-Zahery N, Olivieri A, Pala M, et al. (2009) Y-chromosomal evidence of the cultural diffusion of agriculture in Southeast Europe. Eur J Hum Genet 17: 820–830. doi: 10.1038/ejhg.2008.249
[16] Allison Mann., (2009). Vikings, Merchants and Pirates at the Top of The Wold: Y-Chromosomal signatures of recent and ancient migrations in the Faroe Islands, Thesis Univ. of Louisville. Table 3, pp. 27
[17] Sheyla Mirabal et al., (2009). Y-Chromosome distribution within the geo-linguistic landscape of northwestern Russia. Eur J Hum Genet. 2009 October; 17(10): 1260–1273. doi: 10.1038/ejhg.2009.6
[18] Saric T, An Asian trace in the genetic heritage of the Eastern Adriatic Island of Hvar. International Society for Applied Biological Sciences Abstract number: ABS-282-ISABS-2013
[19] Karachanak S, et al,. (2013). Y-Chromosome Diversity in Modern Bulgarians: New Clues about Their Ancestry. PLoS ONE 8(3): e56779. doi:10.1371/journal.pone.0056779
[20] Y-DNA Haplogroup Q and its Subclades - 2014. The International Society of Genetic Genealogy.
[21] Ville N Pimenoff et al., (2008)., Northwest Siberian Khanty and Mansi in the junction of West and East Eurasian gene pools as revealed by uniparental markers. European Journal of Human Genetics (2008) 16, 1254–1264; doi:10.1038/ejhg.2008.101
[22] The Shetland Y-DNA Surname Project www.davidfaux.org
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2014 by Austin Whittall ©
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