Farewell to the idea of a Jurassic Park: The DNA has a half life of 521 years
It is a complex task to determine the rate of degradation of a molecule of DNA found in the bones of a fossil, mostly because it is not easy to find abundant fossil DNA samples for exact comparisons. This without taking into account the various environmental variables such as temperature, microbes and oxygen.
However, a team of paleontologists published today in the journal response Proceedings B of the Royal Society , estimating that DNA has a half Life of 521 years, that is, in 521 years breaks half of the links between nucleotides forming the sample DNA, then takes another 521 years to break the remaining half of the molecules and so forth.
To calculate this figure, paleontologists, led by Morten Allentoft of the University of Copenhagen and Michael Bunce of Murdoch University – examined 158 samples of DNA in the fossil bones of the legs of the moa , a type of giant bird of New Zealand which became extinct about 500 years ago.
The fossils studied – who were between 600 and 8,000 years old, were recovered from three sites within five miles apart, allowing preservation conditions similar to 13.1° C. This allowed determining a fragmentation rate of 5.50 X 10 ^ -6 nucleotide per year, a rate nearly 400 times slower than predicted by previous studies using DNA in vitro at pH 5.
“This confirms that it is wrong to believe that you can recover dinosaur DNA from prehistoric insects trapped in amber” say scholars like Simon Ho, a computational evolutionary biologist at the University of Sydney.
Now, the next question is to determine this speed varies in other environments such as caves or glaciers, or other factors such as soil type, sample preservation and even the way in which the animal died.
A pity, because it also means that Seymour, J. Philip’s dog Fry never be cloned the year 3000 despite being in dolomite.
– DNA has a 521-year half-life (Nature)
– The half-life of DNA in bone: measuring decay kinetics in 158 dated fossils (Proceedings B)