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Vetinari
Wednesday, May 26th, 2004, 02:56 PM
To investigate which aspects of contemporary human Y-chromosome variation in Europe are characteristic of primary colonization, late-glacial expansions from refuge areas, Neolithic dispersals, or more recent events of gene flow, we have analyzed, in detail, haplogroup I (Hg I), the only major clade of the Y phylogeny that is widespread over Europe but virtually absent elsewhere.

The analysis of 1,104 Hg I Y chromosomes, which were identified in the survey of 7,574 males from 60 population samples, revealed several subclades with distinct geographic distributions. Subclade I1a accounts for most of Hg I in Scandinavia, with a rapidly decreasing frequency toward both the East European Plain and the Atlantic fringe, but microsatellite diversity reveals that France could be the source region of the early spread of both I1a and the less common I1c.

Also, I1b*, which extends from the eastern Adriatic to eastern Europe and declines noticeably toward the southern Balkans and abruptly toward the periphery of northern Italy, probably diffused after the Last Glacial Maximum from a homeland in eastern Europe or the Balkans. In contrast, I1b2 most likely arose in southern France/Iberia. Similarly to the other subclades, it underwent a postglacial expansion and marked the human colonization of Sardinia ~9,000 years ago.

Euclides
Thursday, June 3rd, 2004, 03:29 PM
Am J Hum Genet. 2004 Jul;75(1):128-37. Epub 2004 May 25. Related Articles, Links


Phylogeography of y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in europe.

Rootsi S, Magri C, Kivisild T, Benuzzi G, Help H, Bermisheva M, Kutuev I, Barac L, Pericic M, Balanovsky O, Pshenichnov A, Dion D, Grobei M, Zhivotovsky LA, Battaglia V, Achilli A, Al-Zahery N, Parik J, King R, Cinnioglu C, Khusnutdinova E, Rudan P, Balanovska E, Scheffrahn W, Simonescu M, Brehm A, Goncalves R, Rosa A, Moisan JP, Chaventre A, Ferak V, Furedi S, Oefner PJ, Shen P, Beckman L, Mikerezi I, Terzic R, Primorac D, Cambon-Thomsen A, Krumina A, Torroni A, Underhill PA, Santachiara-Benerecetti AS, Villems R, Semino O.

Department of Evolutionary Biology, University of Tartu and Estonian Biocentre, Tartu, Estonia. sroots@ebc.ee

To investigate which aspects of contemporary human Y-chromosome variation in Europe are characteristic of primary colonization, late-glacial expansions from refuge areas, Neolithic dispersals, or more recent events of gene flow, we have analyzed, in detail, haplogroup I (Hg I), the only major clade of the Y phylogeny that is widespread over Europe but virtually absent elsewhere. The analysis of 1,104 Hg I Y chromosomes, which were identified in the survey of 7,574 males from 60 population samples, revealed several subclades with distinct geographic distributions. Subclade I1a accounts for most of Hg I in Scandinavia, with a rapidly decreasing frequency toward both the East European Plain and the Atlantic fringe, but microsatellite diversity reveals that France could be the source region of the early spread of both I1a and the less common I1c. Also, I1b*, which extends from the eastern Adriatic to eastern Europe and declines noticeably toward the southern Balkans and abruptly toward the periphery of northern Italy, probably diffused after the Last Glacial Maximum from a homeland in eastern Europe or the Balkans. In contrast, I1b2 most likely arose in southern France/Iberia. Similarly to the other subclades, it underwent a postglacial expansion and marked the human colonization of Sardinia ~9,000 years ago.

Euclides
Sunday, October 3rd, 2004, 04:45 AM
Phylogeography of Y-Chromosome Haplogroup I

full article

Euclides
Saturday, October 9th, 2004, 03:12 AM
Phylogeography of Y-Chromosome Haplogroup I

full article



pp129 :

''Interestingly, subclade I1a shows a
distribution similar to the second PC of the synthetic maps
based on classical genetic markers (Cavalli-Sforza et al).''

I am thinking that we probably had a mistake here, because Cavalli-Sforza´s second component is about the distribution of an opposite diffusion of the Uralic gene in Europe related to Basques (Paleo-atlantid). The author was probably talking about Hg Ib2 ( according with the map).

Euclides
Saturday, October 9th, 2004, 04:00 AM
pp134:

"Our time estimates hint that its initial spread in Europe may be linked to the diffusion of the largely pan-European Gravettian technology 28,000–23,000 years ago (Djindjian 2000; Perles 2000). On the other hand, these values represent the lower limit of the age of M170 mutation.''

''The polymorphism M170 represents another putative Paleolithic mutation whose age has been estimated to be ;22,000 years (22, 23). With the exception of idiosyncratic distributions indicative of recent gene flow, M170 is confined to Europe (Eu7). The mutation is most frequent in central Eastern Europe and also occurs in Basques and Sardinians that have accumulated a subsequent mutation (M26) that distinguishes Eu8.''

So Eu7 = HgI , Eu8 = Hg I1b2

"It has been suggested that Gravettian and Aurignac groups coexisted for a few thousand years, maintaining their identities despite occasional contacts. During the LGM, Western Europe was isolated from Central Europe, where an Epi-Gravettian culture persisted in the area of present-day Austria, the Czech Republic, and the northern Balkans (16). After climatic improvement, this culture spread north and east (16). This finding is supported by the present Eu7 haplotype distribution. In this scenario, haplotype Eu8 would have originated in the western Paleolithic population during the LGM,as local differentiation of the M170 lineage.

The frequency and the distribution of haplogroup H across Europe support gene flow between Gravettian and Western European Aurignac groups and suggest differential gender migratory phenomena (24).


Source : The Genetic Legacy of Paleolithic Homo sapiens sapiens in Extant Europeans: A Y Chromosome Perspective


''Evidence suggests the Aurignacians may have been gradually developing the sophisticated tools, trade networks, and expanded use of raw materials that might have ensured their survival. But by 33,000 years ago, a second group of humans, the Gravettians, had largely supplanted the Aurignacian in many areas of Europe. Whether the Gravettians moved into Europe from Central Asia, or, more likely, simply evolved separately in the northern plains of Germany, Poland, and farther east, their improved technology and more complex social organization enhanced their ability to survive in colder climes. ''

"The Gravettians were able to make the social adaptations to survive in a more Arctic climate," said Davies, co-editor of the final report. "By about 30,000 years ago, you see quite large occupation sites. In central Europe there is evidence of the use of plant fibers to make nets and clothing. Clay, bone, and ivory were used in tools and weapons, and the diet expanded to include fish and birds."

By 25,000 years ago, the Aurignacian culture had virtually disappeared, confined to a few small pockets scattered across southern Europe. ''


Source: http://news.nationalgeographic.com/news/2004/02/0209_040209_neandertals.html


''Although there are reported dates for ‘Venus’ figurines ranging from 29,000-14,000 years B.P, by far the majority of the ‘Venus’ figurines appear between 23,000 and 25,000 B.P (Gamble, 1981:97, cited in Dickson, 1990), at a period that is referred to in Eastern Europe as the ‘Gravettian’ and in Western Europe as the ‘Perigordian’. Dickson suggests that the remarkable similarity of the figurines over these vast geographical areas points to these two archaeological traditions being part of the same extended cultural province (1990:65).''

Source: http://www.geocities.com/triple-moon/articles/venusfig.html


My questions are:

1- How did the Gravettians look like?
2- Can we link one of these Hg I subgroups to any modern european race?

beowulf_
Thursday, October 28th, 2004, 02:05 PM
Concerning I1a diversity:

The gene material for France seams extremely thin: 9 persons from regions as distant as Normandy, Provence and the city of Lyon who can source the I1a from differentGermanic invaders - Cimbres and Teutones, Normans, Goths, Franks etc.

According to the study Sweden has a diversity for I1a not much less than that of France (0,93 vs. 0,97). Further, genetically the Swedes are much more homogenous than the French. And despite a much smaller sample size the
French material is from three sides instead of two for Sweden.

Data for central Europe are concealed, but central Europe should be the hinge between the post-glacial recolonialized Northern Europe and the Balkan peninsula which is the glacial refugium for I1b.

So, why not assume that I1a and I1c originated in a group which migrated from the Balkan to Northern Europe after the LGM?