How Long Does DNA Actually Last ?
How Long Does DNA Actually Last ?
With the recent and much publicized discovery of Richard III remains in a parking lot in England, the question of how DNA is maintained over time is being raised more and more.
To determine whether the remains discovered in Leicester are truly those of Richard the III DNA collected from the bones was used and matched with a descendent of Richard’s sister.
The way genetic material is kept plays a very important role in its lifespan, with DNA samples lasting from a couple of months to hundreds of thousands years.
Genetic material decays naturally but the environment it is in as well as its exposure to water sun or oxygen can greatly decrease its lifespan.
Samples that are kept a few feet underground could last as long as 10,000 years. If it is frozen, especially in Arctic conditions, in temperatures that can go as low as -80 degrees Celsius the same sample could last a couple hundred thousand years.
Some sources say that the lifespan of DNA could be greater than anything science has ever imagined, lasting millions of years in the right conditions. Claims have been made that genetic material that is 419 million years old has been discovered in salt deposits in the Michigan Basin. Most scientists, however, question that this is possible as research shows that all genetic material would be destroyed or rendered useless by radiation long before it reached one million years.
Also the myth that amber plays an important role in maintaining genetic material is quite false, as scientists have shown, amber is great for preserving skeletons especially those of small insects, however, the genetic material inside the trapped insect would quickly expire after its death.
The same goes for mummies. While they might look perfectly preserved on the outside with muscle tissue, skin and even hair in some cases, the DNA has broken down a long time ago, especially thanks to the heat most mummies are exposed to.
The oldest recovered genetic material comes from Greenland and is anywhere from 450,000 to 800,000 years old. The recovered material belonged to pine trees, and butterflies.
The oldest Neanderthal DNA recovered is close to 100.000 years old while the oldest human DNA is just 7000 years old.
Cloning species or humans that have long died or been extinct has been the subject of quite a few sci-fi books and movies, however, such an undertaking would present huge difficulties as all recovered genetic material is altered to some degree, regardless of the conditions it was kept in.
Spanish researches came closest when they managed to bring back an extinct ibex specimen. Sadly, the animal died of breathing problems after just seven minutes because of the faulty DNA.
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