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Jean M
03-22-2013, 02:29 AM
Qiaomei Fu et al., A Revised Timescale for Human Evolution Based on Ancient Mitochondrial Genomes (http://www.cell.com/current-biology/abstract/S0960-9822%2813%2900215-7), Current Biology, 21 March 2013.


All but one of the ancient modern human sequences from Europe belonged to mtDNA hg U, thus confirming previous findings that hg U was the dominant type of mtDNA before the spread of agriculture into Europe. The exception was the Cro-Magnon 1 sample, which belonged to the derived hg T2b1, an unexpected hg given its putative age of 30,000 years. Since the radiocarbon date for this specimen was obtained from an associated shell, we dated the sample itself using accelerator mass spectrometry (AMS). Surprisingly, the sample had a much younger age of about 700 years, suggesting a medieval origin. Consequently, this bone fragment has now been removed from the Cro-Magnon collection at the Musee de l’Homme in Paris. ...

It has been argued that hg U5 is the most ancient subhaplogroup of the U lineage, originating among the first early modern humans in Europe. Our results support this hypothesis because we find that the two Dolni Vestonice individuals radiocarbon dated to 31.5 kya carry a type of mtDNA that is as yet uncharacterized, sits close to the root of hg U, and carries two mutations that are specific to hg U5.


Their table 1 shows a sample from Paglicci Cave as H1, but the text rejects this sample, which appears not to be ancient. (Contamination maybe.) The authors have been very careful.

The new sequences are in my Ancient Western Eurasian DNA (http://www.buildinghistory.org/distantpast/ancientdna.shtml) table.

J Man
03-22-2013, 02:43 AM
Wow this is huge!

GailT
03-22-2013, 05:11 AM
Yeah, this is the paper I was hoping for - if they could do a full sequence for Neanderthals and Denisovans, I hoped they could do the same for pre-ice age modern humans. Very exciting. The also establish to some extent the order in which U5's string of 5 mutations occured - some of the samples have just 2 of the 5 defining mutations for U5.

From the Dicussion section of the paper:


We were able to reconstruct three complete and six nearly
complete mitochondrial genomes from ancient human
remains that were found in Europe and Eastern Asia and
span 40,000 years of human history. All Paleolithic and
Mesolithic European samples belong to mtDNA hg U, as
was previously suggested for pre-Neolithic Europeans [15].
Two of the three individuals from the Dolni Vestonice triple
burial associated with the pre-ice age Gravettian culture,
namely, 14 and 15, show identical mtDNAs, suggesting
a maternal relationship. Furthermore, both individuals
display a mitochondrial sequence that falls basal in a phylo-
genetic tree compared to the post-ice age hunter-gatherer
samples from Italy and central Europe, as well as the
contemporary mtDNA hg U5 (Figure 1). It has been argued
that hg U5 is the most ancient subhaplogroup of the U
lineage, originating among the first early modern humans in
Europe [18]. Our results support this hypothesis because
we find that the two Dolni Vestonice individuals radiocarbon
dated to 31.5 kya carry a type of mtDNA that is as yet un-
characterized, sits close to the root of hg U, and carries
two mutations that are specific to hg U5. With our recali-
brated molecular clock, we date the age of the U5 branch
to approximately 30 kya, thus predating the LGM. Because
the majority of late Paleolithic and Mesolithic mtDNAs
analyzed to date fall on one of the branches of U5 (see
also [15]), our data provide some support for maternal
genetic continuity between the pre- and post-ice age Euro-
pean hunter-gatherers from the time of first settlement to
the onset of the Neolithic. U4, another hg commonly found
in Mesolithic hunter-gatherers [15], has so far not been
sequenced in a Paleolithic individual, and we find hgs U8
and U2 in pre-LGM individuals but not in later hunter-gath-
erers. At present, the genetic data on Upper Paleolithic,
and especially pre-ice age, populations are too sparse to
comment on whether or not this is representative of a change
in the genetic structure of the population, perhaps caused by
a bottleneck during the LGM and a subsequent repopulation
from glacial refugia.