Neanderthal Genome Video Update (4/25/2007)
Nature has put a wonderful short set of videos on their web site about the Neanderthal Genome Project. The project, which hopes to decode and publish the Neanderthal Genome, within a couple years, is steadily making progress, and is releasing new information in regular intervals.
You can read some previous articles about Neanderthals here.
The videos, which you can find here in Nature's Video Archive, are broken up into 4 sections: Introduction, New Techniques, Analysis, and Conclusions:
The introduction goes into the whys of the whole project. Why sequence Neanderthal DNA? Because Neanderthals are the closest relatives to modern humans, what we can learn about their DNA will ultimately tell us a lot about our own DNA. Why did the Neanderthals die out? The fact is, we don't know. Several theories exist, but their isn't enough evidence to make any one of them seem a likely winner. By sequencing Neanderthal DNA, we may be able to find out if their extinction was due to genetic diseases, or susceptibility to viruses, or possibly even diet and nutrition. It may even lead to a new understanding of genetic diseases in modern humans.
The introduction also interviews three of the individuals working on the project. These guys must be loving life. I can't imagine working on a project that is both as exciting as genetic archaeology, while at the same time as mind numbingly boring as waiting for a machine to spit out a chunk of sequenced DNA. I'm not sure I could handle the wait. The folks introduced are:
- Ed Green, Computational Biologist
- Johannes Krause, Biochemist
- Adrian Briggs, Molecular Biologist
Because Neanderthal DNA is several tens of thousands of years old, it has degraded while at the same time has been contaminated by other organisms which have come into contact with the remains. Using a new shotgun technique, they are extracting and amplifying all of the DNA, and slowly stitching it back together. Though this process should be much faster at collecting the DNA, it will undoubtedly take a lot of time on the analysis process.
They claim to have decoded 1 million base pairs, which sounds like a lot, but is really a drop in a lake. If the Neanderthal DNA is similar in number to humans, then they still have a REALLY long way to go. Humans have approximately 3 billion DNA base pairs.
In the Analysis section of the videos, they talk more about the techniques for extracting the DNA. This isn't surprising though since analysis can't really being until a majority of the DNA has been extracted and sequenced.
They talk more about how they separate each DNA sequence then amplify the DNA, so that they have millions of copies to study. They also explain how they intend to remove contaminated DNA from the final sequence, during the analysis portion.
They didn't talk much about the 454 Life Sciences sequencing machines they are using, but I imagine that is because they are under a non-disclosure agreement of some kind. These new machines are using a very different method of DNA extraction, than those used on the Human Genome Project and are being donated (along with support) to the project by 454 Life Sciences. Hopefully more will be discussed about them in the future.
The conclusions portion of the videos, talks about whether humans and Neanderthals interbred, or more specifically if gene flow occurred between both species. The reason for this continuing question, is that humans seem to have so many unique abilities like culture and language, that scientists wonder when we learned them.
Did Neanderthals have language? The debate will probably continue long after the Neanderthal Genome is sequenced, but it will allow for comparative analysis. In previous articles about genes and intelligence, genes for memory, intelligence and other neuro-genes have been identified, and will certainly be targets for these comparative studies.
Though these videos were wonderful, I can only hope a more information continues to come out of this project on a regular basis.