Paleontology

Clone Dinosaur Dna Extinct Fossil Proteins



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Yes, and there are at least three major sources of DNA: fossilized amber, inactive "psuedogenes," and dinosaur fossils themselves.  The first and best known sources taken from amber fossils as shown in the famous film, Jurassic Park, wouldn’t supply scientists with enough material for a complete set of dinosaur genes.  Searching the blood cells trapped inside the gut of mosquitoes in fossilized amber present a problem because warm blooded dinosaurs use simple platelets, like human beings, mammals, and birds.  For blood, reptiles and amphibians use actual cells with DNA in them, but in bird-like dinosaurs, only the rare white blood cells would contain any usable DNA. 

Scientist Raul Cono was successful using a relatively new technique in 1992 extracting genetic material from fossilized amber, producing DNA from a 40 million year old bee.  Using the same method, researchers from the American Museum of Natural History uncovered termite DNA from one block of amber.

www.youtube.com/watch?v=XnudC9INVJ0

Inside fossilized bones, however, are tiny fragments of DNA still present.  Even if we were to grind up all of the world’s tyrannosaurus fossils, we wouldn’t have enough fragments to produce even a single copy of DNA.  Nevertheless, paleontologists may be able to use these fragments as a kind of cheat sheet to verify incomplete DNA from other sources.  Dr. Timothy Rowe of the University of Texas (among others) has cast skepticism on this technique. “DNA doesn’t have a long survivability in the fossil record.  It’s really exceptional to get DNA that’s more than a few thousand years old.  So, we’ve pulled DNA out of dinosaur bones, but it didn’t belong to dinosaurs.” Rowe warns that the insects found inside of amber had been digested long ago by bacteria, leaving only the exoskeletons inside.  Worse, the complex molecules found in fossils start to degrade as soon as samples are taken from the ground and exposed to the weather.  It can take days before a fossil will reach a university to be analyzed.

On the other hand, famed paleontologist Jack Horner of Montana State University obtained funding to bring an on site Mobile Dino Lab to a dig site in order to extract time sensitive information from these fossils.  The specimens must be destroyed in order to extract chemical information, but Horner says, “I think we have a great opportunity to get much better protein, and possibly even DNA samples from these dinosaurs by getting the lab close.  The first thing... we actually pluck some of the pieces out the big bones and send them to our molecular lab to process.” Since the lab is on site, next to the dig, more moleculor information can be derived from these fossils.

news.discovery.com/videos/dinos-analyzing-dinosaur-fossils.html

When protein sequences from T-Rex were examined by scientists, the closest match they could find with living organisms was from a chicken.  Finding genetic material may be much more difficult. “In fact, DNA has really only been isolated from fossils maybe 100,000 years old,” adds commentator Jan Witkowski “but then, before this paper, people didn’t even think that you could get protein from such old fossils.”

The second viable source may be the most productive of all, and may supply us with a complete set of at least one species of dinosaur, the Struthiomimus, itself an ancestor of the ostrich, ewe, and extinct elephant bird.  According to an article in TIME Magazine, “[G]eneticists are finding many ‘pseudogenes’ in human and animal DNA-copies of old, discarded genes... There may be a lot of interesting obsolete instructions hidden in our genes.”

www.time.com/time/magazine/article/0,9171,996609,00.html

In fact, it’s been found that most mutation in an species’ genome are additions tacked on to the genes-rather than changes-which then create changes in the adult.  Baby raptors have been found in the egg with down feathers looking almost like chicks.  If the infants do not need to evolve or adapt, they tend to remain similar over the millennia.  Still, each new gene creates changes in the adults, such as those converting dinosaur teeth into tiny serrations on bird beaks.  If the mutation is removed, a new embryo can be grown with teeth, claws, even a longer tail or a shorter, simpler, carnivorous digestive tract.

Remnants of blood vessels and perhaps cells have been found inside one of the larger fossils of a tyrannosaurus femur in December of 2007 at a Montana site.  Professor Mary Schweitzer of NCSU offers, “The potential is there to really find some differences, but that’s not something we can address... It’s not something we’re anywhere close to doing.” Because these blood vessels and structures are so similar to those of the ostrich, however, we may be able to start with that animal as a basis for the project.  

A late cretaceous ancestor of ostrich was the 14 foot long Struthiomimus.  Found in large numbers in the fossil record, it is likely also a vegetarian, unlike many of ostrich’s modern relatives.  By mapping the genomes of several species of primitive birds, including the ostrich, similarities may be found, producing the genome of a common ancestor.  From that basis, fragments of T-Rex DNA, or another target species, may be used to check and correct this genome, eventually leading to the gestation of a somewhat accurate Tyrannosaurus Rex inside of an ostrich egg.  After reaching the adult stage, the bone structure of the prototype animal or animals could be compared with known fossils-even the skin and tissue, as with a recent mummy of Hadrasaurus-eventually producing a near perfect match.

Although aurochs went extinct in Europe around 1627, scientists are currently attempting to clone these 2,200 pound animals by mapping their genome and inserting these genes into a bovine egg, to be gestated inside the womb of a large cow.  Although the mammoth went extinct around 1700 BC, scientists are now attempting to clone on based on the DNA of a recently uncovered mammoth unearthed in 2008. There are 400,000 gene sites that differ between an African elephant and the woolly mammoth, but it is expected to cost about $2 million to map out this genome, and $10 million altogether to bring an example back to life.

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