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DARPA Sponsoring Limb Regeneration Research
fragmentate writes "Wired News is reporting: 'In response to the hundreds of soldiers coming home from war with missing arms or legs, Darpa is spending millions of dollars to help scientists learn how people might one day regenerate their own limbs. Prosthetics are getting better all the time, but they will never be as good as the limbs we were born with. So two teams of scientists at 10 institutions across the country are competing to regrow the first mammalian limb ... The researchers' first milestone is to generate a blastema — a mass of cells able to develop into various organs or body parts — in a mammal.' Apparently this is a relatively new area of research, even Wikipedia's stub on blastemas is very terse."
(WARNING - SPOILERS)
When William Mandella lost his leg in an accident he was under the impression that he would simply be given an artificial one and would then be free to persue a semi-normal life. To his horror he discovers they'll simply grow him a new leg and chuck him right back in to active duty... :)
THE HONOUR OF THE KNIGHTS - CC Licensed Sci-Fi Novel
Why not? I see no good reason why competent engineering can't eventually beat a chunk of meat.
It's not like we were intelligently designed... we evolved. Evolution will tend to produce good solutions to problems, but it will hardly ever produce the best possible solution. Once we get nerve-circuit interfaces down, we should have no problem outengineering most of the human body.
-- The act of censorship is always worse than whatever is being censored. Always.
The two groups are sharing $7.6 million in grants for a year to find a way to give humans salamander-like abilities.
Am I out of whack or it's $7.6m like peanuts for this kind of research? I'd guess any serious effort on that would need to be in the billions level, and that likely for many years.
Rome taught me patience and assiduous application to detail. Virtues which temper the boldness of great, general views.
First of all, TFA says that one of the two teams of scientists working on this is basing their work on the MRL mouse, which can and does regenerate internal organs, including severed spinal cords.
Second of all, this may increase lifespan, but would not provide immortality. Human cells stop reproducing after a certain number of reproductions. The cell chromosomes have end-cap like things called telomeres which are shortened with each mitotic cycle. When they get too short, the cell stops reproducing. This is to prevent too many mutations from accumulating after a while. Generally, if cells divide without shortening the telomeres, they're usually malignant tumor cells. So to get immortality, you'd have to augment the mitotic cycle to a) "spellcheck" the chromosome copying, and b) prevent the telomeres from being shortened.
I claim first use of "Error No. 0B" - or "No. 0B error." It'll be the new ID 10T!
If they can regenerate organs, will they be able to regenerate the largest organ, skin? This would help burn victims immeasurably.
Drastically reduce but not eliminate. IIRC mutations tend to occur once every 600,000 base pairs, so that would mean that replication is about 99.99983% accurate. After 100 divisions the genome of a cell would only be 99.983% accurate, so it'd have about 1 error every 500 base pairs. Given the size of most genes/proteins, that cell should have some serious problems or be cancerous. (I don't know the "maximum" number of divisions, it could be more or less, but you can see the problem.) Not to mention, mutation accumulation is just one part of aging. Now, if we could take our genome and add some parity base pairs and some redundancy checking proteins we might be able to address that problem. But that's far beyond our level of genetic engineering (AFAIK).
As I understand it, the ability of cells in a human body to regenerate themselves (heal) diminishes over time due to "programming" in our genes. This causes aging, but is also a cancer fighting mechanism.
If you could use a given adult's body to grow a blastema or whatever it is and then use it to grow a limb or organ, the cells would remember their "age" and would still not be as resilient as a child's organ or limb. Therefore, you could replace your heart at the age of 75 but it would still be a 75 year old's heart in some ways.
If you could use a child's cells to create a blastema and then use that to create organs for an adult, then you're talking about real rejuvenation. Of course, you'd not be able to do this with a brain, so you're still going to eventually run out of neurons. At least you could live a better quality of live though.
The best idea would be to combine this blastema thing with the ability to turn off the genes that cause aging, while finding a cure for cancer at the same time. Then I think we would be almost immortal. Just keep your brain from being damaged beyond repair.
"I have never let my schooling interfere with my education." - Mark Twain
Heinlein, is that you?!
Circumcision is child abuse.
A member of each tem gets one limb sawn off and the first one to regrow it to appropriate size wins the prize!
"Enjoy what you're doing! If it becomes drudgery, you're doing it wrong!" - Jim Butterfield
Actually, humans have an enzyme called telomerase that rebuilds telomers. You're right that telomers do wear down over time, but the solution may be much simpler than preventing telomer shortening, which, if I remember correctly, is sort of a side-effect of DNA replication.