May 18, 2008

Paleogenetics of cattle domestication

Research on modern cattle had suggested the Neolithic Near Eastern origin of domesticated cattle, but also that some of the European aurochsen transmitted their mtDNA to European cattle. By looking at prehistoric mtDNA, the researchers were able to discover that the Neolithic to Bronze Age cattle of Europe lacked the native aurochs mtDNA and were exclusively descended from the domesticated animals brought into Europe from the Near East.

From the paper:
Therefore, it is of utmost importance to control the PCR. This is possible when using a quantitative approach, and, in particular, quantitative real-time PCR (QPCR), which allows for online monitoring of the PCR and quantification of the amplified DNA thanks to the use of fluorescent probes [49].


Therefore, QPCR is, to my mind, the best method for amplification of ancient DNA. Up until now, however, it has rarely been used and not a single study of the genetics of ancient populations or of a domestication process has been conducted using this method. We have adapted QPCR to ancient DNA research and used it for our study of the domestication process of the aurochs in Southwest Asia with a so far unequalled success rate. We have thus been able to appreciate better:

• DNA conservation, during and after burial;
• contamination with modern DNA;
• base modifications and amplification errors.

The method has proved to be a key asset in the study of DNA preserved in fossilising bones that have been subjected to climatic and/or chemical conditions that are
unfavourable to DNA preservation. This will be discussed hereafter.


The combination of the use of freshly unearthed, unwashed fossil remains and our quantitative high-fidelity and high-sensitivity PCR approach allowed us to obtain some 60 authenticated mitochondrial sequences from between 9500- and 3000-year-old bovine remains, 30 from Southwest Asia and 30 from western Europe (mainly France) (Pruvost et al., in preparation).


The result of this large-scale analysis proves on the genetic level that it was the aurochs population from the Upper Euphrates and Tigris Basin that had been domesticated almost 10,000 years ago and then spread into Europe, since Neolithic and Bronze Age cattle in western Europe show a mitochondrial signature that is a subset of that of their ancestral populations in Southwest Asia (Pruvost et al., in preparation). They also gave rise to the extant cattle populations all over the world, although modern-day cattle in continental Europe represent only a small subset of the original populations (Pruvost et al., in preparation). In contrast, the western European aurochsen did not leave a mitochondrial signature in extant European cattle, which indicates that female western European aurochsen were not domesticated in Europe, but rather maintained their status as hunted game until at least the Bronze Age (Pruvost et al., in preparation).
Comptes Rendus Palevol doi:10.1016/j.crpv.2008.02.001

Palaeogenetics of cattle domestication: Methodological challenges for the study of fossil bones preserved in the domestication centre in Southwest Asia

Eva-Maria Geigl


Recently, palaeogenetics encountered enormous success when parts of the nuclear genomes of mammoth and Neanderthal man were analysed. Their bones, however, had been preserved in environments favourable to DNA preservation, i.e., permafrost regions
and caves in temperate regions. Few studies have tackled archaeological bones from hot, arid regions, although they bear great significance for the study of evolution of humans and the precursors of modern societies. According to archaeological evidence, a key event in neolithisation, the domestication of cattle, took place around 10,000 years ago in Southwest Asia. Genetic data from prehistoric bovine bones preserved in this region might shed light on this process, but the palaeogenetic approach has been hampered by poor DNA preservation. Here, I discuss various aspects of DNA preservation in fossils and the production of reliable palaeogenetic data and present methodological improvements that have enabled us to shed light on the process of cattle domestication in Southwest Asia and its spread into western Europe.



miz RAND BLOWTON said...

These cow articles seem to imply that since cows aren't from Europe it's not really the Europeans's cows;but most food is viewed universally as a commidity and is used and exchanged freely.For instance,why not mention that bananas and potatoes,and chocolate don't come from Europe,and neither does corn and sunflowers/seeds,nor do dates and tuna fish,but that doesn't mean we don't use them.We figure,if it isn't hurting the natives,nor making us break out in warts,why not use food found on the land..?Oh,and cotton isn't from Europe neither.Also people don't marry other types of people to aquire other foods or goods-English didn't marry Native Indians to get corn-the Indians gave us some corn and we grew it-no need to marry foreign to get some goods.The Indians got whisky,guns,and horses from the white man,too. Further more the earth was all one place called Pangaea,and we all got off Noah's Ark in Asia Minor somewhere with many animals in tow,so it might have all been connected to one location years ago.Besides all animals and palnts aren't fit for food,even if they grow naturally on your land;I mean,why don't we eat roaches since we have plenty of those,but they are from Africa not Europe,anyway.Most food in Africa is not from Africa-many foods were brought there by Arab merchants or something-except coffee-but the Africans didn't use it until a Caucasian Priest discovered it.Now of course if you want to go back to livin' like a cave be authentic.

miz RAND BLOWTON said...

"but most food is viewed as a COMMODITY",I meant to say. COMMODITY means"an article of commerce,especially when delivered for shipment". Also each nation "owns" their own products by selecting a certain breed of corn or cow and refining it to their tastes and making it their own ,for their own consumption then it belongs to that nation,by their efforts to choose it,preserve it,nurture it for themselves.