I would love to try that with my left foot which has made me suffer from pinched nerves and incredible persistent electrical pain for 4 years now. I guess I'll just chop it off now and see if my genes are up to the task! Kidding.

Too bad the human mind, not brain, body, cells or gens, the human mind has a maximum tolerable length of life past which you just slowly become a zombie even if your body and organs are in best shapes.
Imagine living in eternity. Any eternity. Yup eventually you'd reach a point where anything in any scenario becomes hells. Well that point is usually reach when you live past a hundred of years or so depending on what you live, because ultimately you've seen, felt and experiences it "all", and no new technology or events could make you feel "alive".

All they need to do is read spiderman vs the lizard and hey presto.

The acorn worm tries to live in unpolluted water: lets watch its future as pollution spreads. How well does it cope with our industrial cocktail !

I can already see a huge problem with this science. As with the worm, wouldn't another you be created as the severed limb begins to grow into another you. I guess you could somehow dispose of the severed limb to keep it from regrowing, but couldn't that be construed as murder. You see that there are a number of issues that would have to be worked out before taking such a step. It never ceases to amaze me how, as we always do, people love the potential newly discovered science brings, but they don't consider the consequences it's implementation would bring.

Gmayle, I'm pretty sure you'd need your internal organs working to allow your body to regenerate an arm. The severed appendage would just rot without a blood supply. Now if you could keep that severed arm alive with some outside source of blood then I could see where you are coming from with your worry of the arm growing another body. That would be a pretty good horror movie.

Let's not forget the time scales here people. Let's say you did cut off your limb. You have a tiny infant limb in about 1 year, a juvenile limb for about another 12 years and then finally some kind of Adolescent and teenager limb. Your full adult limb would not be there for about 17 years. It would appear pristine and much younger than your other leg. With this long waiting time and this mismatch to the limb would it be worth it?

BobM Best guess, it will start will Stem Cell regeneration. And, yes a modified method to speed up the growth process will be necessary to make it feasible for immediate medical attention. IMO

Gmayle....relax. This is bogus and will not happen. Most likely ever and definitely not in our life time. And if it does, it will cost an arm and a leg!

First, genetics are not the full information that forms organisms, especially in cellular construction of organs. Internal Cellular Matrixes have been implicated in vastly complex activities previously thought to be the domain of DNA. There's two halves to the puzzle and we don't even know how to read half of it right now.
SO I wouldn't hold your breath that they'll be able to tackle this without the full picture.
Second, they should look closer to humans first. As in mammalian. Much higher chance that the African spiny mice (particularly Acomys kempi and Acomys percivali) will be able to help us regenerate than something that doesn't even have a backbone.