DNA preserved in bones undergoing fossilization deteriorates up to 50 times faster when stored in a museum than when the bones are buried in the ground. This has just been shown by a paleogenetics team led by Eva-Maria Geigl (Institut Jacques Mono / CNRS Paris). This study, which was published in the Proceedings of the US National Academy of Sciences 8 January 2007, shows that in order to improve the quality of paleogenetic analyses, archeological and paleontological remains should be treated like biological samples both during and after excavation. The findings show the need for a new methodology for the excavation, treatment and preservation of fossils. They also open up new prospects for paleogenetic research into freshly excavated fossils.
In paleogenetic research, it is essential to have well-preserved archeological material in order to obtain reliable results. At present, such research is only too rarely the result of close collaboration between the various disciplines involved: molecular biologists, archeologists, paleontologists and curators. Moreover, biologists mostly carry out such studies on samples stored in collections or in museums. However, there was no reason to suppose that the treatment carried out by fieldworkers (archeologists, paleontologists and curators), as well as storage conditions, were compatible with a paleogenetic approach. In fact, such analyses were often subject to a high failure rate, due partly to a lack of any ancient DNA detected by PCR , or to contamination by modern DNA.
An extensive study of around 250 fossil bones from 600 to 50 000 year old herbivores was carried out thanks to international cooperation between the Institut Jacques Monod at CNRS, the Museum of Natural Sciences in Madrid and a number of European, Turkish and Japanese paleontologists and archeologists. The work showed that mitochondrial DNA from freshly excavated, untreated fossil bones was amplified with a success rate of 46%. How
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