Ancient DNA

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Ancient DNA can be loosely described as any DNA recovered from biological samples that have not been preserved specifically for later DNA analyses. Examples include the analysis of DNA recovered from archaeological and historical skeletal material, mummified tissues, archival collections of non-frozen medical specimens, preserved plant remains, ice and permafrost cores, Holocene plankton in marine and lake sediments, and so on. Unlike modern genetic analyses, ancient DNA studies are characterised by low quality DNA. This places limits on what analyses can achieve. Furthermore, due to degradation of the DNA molecules, a process which correlates loosely with factors such as time, temperature and presence of free water, upper limits exist beyond which no DNA is deemed likely to survive. Current estimates suggest that in optimal environments, i.e environments which are very cold, such as permafrost or ice, an upper limit of max 1 Million years exists. As such, early studies that reported recovery of much older DNA, for example, from Cretaceous dinosaur remains, have been proven to be wrong, with results stemming from sample or extract contamination, as opposed to authentic extracted DNA.

For more information about Ancient DNA, read the full article at Wikipedia.
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News tagged with ancient dna


DNA study sheds new light on horse evolution

DNA study sheds new light on horse evolution

Biology / Evolution

created Dec 10, 2009 | popularity 5 / 5 (4) | comments 62

(PhysOrg.com) -- Ancient DNA retrieved from extinct horse species from around the world has challenged one of the textbook examples of evolution - the fossil record of the horse family Equidae over the past ...





Search results for ancient dna


Late-surviving megafauna exposed by ancient DNA in frozen soil

Late-surviving megafauna exposed by ancient DNA in frozen soil

Biology / Biotechnology

created 20 hours ago | popularity 4.5 / 5 (2) | comments 0

Extinct woolly mammoths and ancient American horses may have been grazing the North American steppe for several thousand years longer than previously thought. After plucking ancient DNA from frozen soil in ...


mammoth

The mammoths' swan song revised

Other Sciences / Archaeology & Fossils

created Dec 14, 2009 | popularity 4.4 / 5 (12) | comments 3

This is shown by samples of ancient DNA, analysed by an international team of research scientists under the leadership of Professor Eske Willerslev from Copenhagen University. Analyses of ancient DNA thereby ...


Just like old times: Generating RNA molecules in water

Chemistry / Biochemistry

created Nov 20, 2009 | popularity 4 / 5 (3) | comments 0

A key question in the origin of biological molecules like RNA and DNA is how they first came together billions of years ago from simple precursors. Now, in a study appearing in this week's Journal of Biological Chemistry, resear ...


Scientists Unravel Evolution of Highly Toxic Box Jellyfish

Scientists Unravel Evolution of Highly Toxic Box Jellyfish

Biology / Plants & Animals

created Nov 18, 2009 | popularity 4 / 5 (5) | comments 1

(PhysOrg.com) -- With thousands of stinging cells that can emit deadly venom from tentacles that can reach ten feet in length, the 50 or so species of box jellyfish have long been of interest to scientists ...



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