We are a big step closer to Jurassic-Park-style species resurrection.
The U.S. Department of Energy’s Joint Genome Institute has sequenced the DNA for the extinct Pleistocene cave bear species. In the past scientists have found it next to impossible to extract useful DNA from such old samples. While some information was thought to remain, broken and scattered, most of the DNA in these old samples was microbial contamination.
So, hoping that there would be enough DNA within these samples to learn something, DOE scientists used a brute force high throughput sequencing approach that was developed for sequencing modern samples. It worked. 6% of the sample was broken pieces of cave bear DNA. That was enough to get a complete sequence. A piece of DNA was found here, a piece there, and then it was reassembled using dog DNA as a template.
…within that [6%] fraction, there was a range of genomic sequence types, including fragments of 21 genes, identified by comparing the cave bear sample to the complete dog genome sequence that exists in the public databases. Dogs and bears, which diverged some 50 million years ago, are 92 percent similar on the sequence level.
Unfortunately, the scientists involved don’t think it will be possible to use this method to resurrect dinosaurs. The current theoretical limit of this technology is said to be 100,000-year-old samples, perhaps longer for frozen samples. I wonder though if it would be possible to do this with the T-rex soft tissue that was recently recovered complete, perhaps, with blood vessels and cells.
“We picked cave bear as an initial test case ancient DNA target because the samples we used in the study are roughly the same age as Neandertals,” Rubin said. “Our real interest is in hominids which include humans and the extinct Neandertal–the only other hominid species that we have to compare with humans. Our nearest living relative is the chimp and that’s five million years of divergence. Although we are very similar on a sequence level, there are obvious phenotypic differences. Next, we would like to access and evaluate genomic information about other hominid species, Neandertals in particular, as they represent probably our closest prehistoric relative.”
None of these scientists are thinking about cloning a Neanderthal. One or two ethical issues come to mind. But, a full sequence of the Neanderthal DNA would be a gold mine for the study of human prehistory. There is interest also in sequencing the Flores Man – the newly discovered “hobbit” species that is thought to descend from Homo erectus. Comparing these sequences with modern humans and with other close relatives like Chimpanzees will reveal much about human evolution.
While human cousins will remain safely extinct, most of us would love to see the cave bears brought back. In fact, within the 100,000-year limit, there’s a whole menagerie of animals that the world would come to see.
Take Andromeda, our plucky little next door neighbor in the universe. It will be a while before we find that the entire core of that particular galaxy has been subsumed by a vast, Borg-like hivemind intent on swallowing everything in its path and that means us (once again, you read it here first), but that doesn’t mean that Andromeda doesn’t have a lot of secrets left to reveal. For example, the fact that it’s actually 
