Posts Tagged ‘Mitochondrial DNA’

DNA sequenced from a 400,000 year old hominin from Spain

December 4, 2013

After developing techniques for extracting and analysing DNA from ancient (c. 40,000 years ago) Neanderthal and Denisovan specimens the Max Planck team have now taken a giant leap backwards in time in extracting and analysing an almost complete mitochondrial genome sequence of a 400,000-year-hominin. The specimen is from  Sima de los Huesos, a unique cave site in Northern Spain. The results show that it is related to the mitochondrial genome of Denisovans, extinct relatives of Neandertals in Asia. DNA this old has until recently been retrieved only from the permafrost.

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The Sima de los Huesos hominins lived approximately 400,000 years ago during the Middle Pleistocene. © Kennis & Kennis, Madrid Scientific Films

The result itself is of great interest but it is the development of the techniques for extracting and analysing – without any contamination – and with sufficient confidence, the entire MtDNA sequence in such old specimens that is quite revolutionary. Archaeological evidence – and particularly of of such age – is subject to a great deal of subjective interpretation. But dating techniques and now DNA extraction techniques are removing much of this subjectivity and they are now providing the anchor points around which the evolutionary narrative must be built. And this narrative is now of a much more complex story of hominin expansions and admixture than has generally been thought. Ancient and presumed extinct hominin species are now showing themselves within us.

“Our results show that we can now study DNA from human ancestors that are hundreds of thousands of years old. This opens prospects to study the genes of the ancestors of Neandertals and Denisovans. It is tremendously exciting” says Svante Pääbo, director at the Max Planck Institute for Evolutionary Anthropology.

Matthias Meyer, Qiaomei Fu, Ayinuer Aximu-Petri, Isabelle Glocke, Birgit Nickel, Juan-Luis Arsuaga, Ignacio Martínez, Ana Gracia, José María Bermúdez de Castro, Eudald Carbonell, Svante PääboA mitochondrial genome sequence of a hominin from Sima de los HuesosNature, 2013; DOI: 10.1038/nature12788

Read the whole post in 6,000 Generations

 

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The ancient melting pots of Europe

October 11, 2013

Stone Age settlers migrated across Europe in multiple waves that replaced older hunter-gatherer cultures with the genes from each wave blending into the population of the day. Ancient mtDNA studies are revealing that cultures spread to a great extent by the physical migrations of peoples and possibly faster and more effectively than by cultural diffusion alone. And the many different gene-melts continue today. Whereas in the Stone Age much of the action was in Central Europe, in the jet-age the melting-pots have shifted westwards and are mainly now in Western and Northern Europe. The peopling of Europe is an ongoing thing.

Guido Brandt, Wolfgang Haak, Christina J. Adler, Christina Roth, Anna Szécsényi-Nagy, Sarah Karimnia, Sabine Möller-Rieker, Harald Meller, Robert Ganslmeier, Susanne Friederich, Nicole Nicklisch, Joseph K. Pickrell, Frank Sirocko, David Reich, Alan Cooper, Kurt W. Alt and The Genographic Consortium, “DNA reveals key stages in the formation of Central European mitochondrial genetic diversity,” Science doi: 10.1126/science.1241844

National Geographic:

… the people who lived in Central Europe 7,000 years ago had different DNA lineages than those that lived there 5,000 years ago, and again different to those that lived 3,500 years ago. Central Europe was dynamic place during the Bronze age, and the genetic composition of the people that lived there demonstrates that there was nothing static about European prehistory.

Genographic Project Director and National Geographic Explorer-in-Residence, Spencer Wells expounds: “spanning a period from the dawn of farming during the Neolithic period through to the Bronze Age, the [genetic] data from the archaeological remains reveals successive waves of migration and population replacement- genetic ‘revolutions’ that combined to create the genetic patterns we see today.”

What we see in Europeans today is a kind of mixture of what was present there at different times in our past. So, just like parts of Europe today are melting pots from different living cultures across the world, Europe is also a melting pot of genetic lineages from different prehistoric cultures that lived there at different periods of time.

timeline peopling of europe Brandt et al, DOI: 10.1126/science.1241844 fig.3

 

Dienekes: “Central Europe, once populated exclusively by hunter-gatherers, experienced a virtual disappearance of their matrilineages for almost two thousand years after the advent of farming.  Then, between the Middle to Late Neolithic, around five thousand year ago, the hunter-gatherers make their re-appearance before their lineages converge to their modern (minority) frequency”


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