Cellular Regeneration in Humans

What if there was a way to regrow a limb or finger or anything else that a person may have lost? Like in a lab accident. That sentence was just so I could use this picture of Dr. Connors.

That aside, I've heard rumors about a baby being able to regrow the end of a digit of a finger after its been severed. Why the fuck would you cut off the end of a babies finger is beyond me, but the concept isn't as far fetched as you might think.
Within us, we have a gene (identified as p21) that regulates cell growth. Studies have been run that show that mice lacking this gene have the potential to regrow damaged or severed parts. So why not do this for humans!? It will give you super cancer, thats why not. Or at least potentially, because p21 is tightly controlled by p53 which is basically a tumor suppressor. The lack of this gene in humans would probably lead to a complete lack of cellular regeneration limiting, leading to the growth of too many unnecessary cells. The absence of p21 provides the mice and animals with this gene absent the ability to form blasterma instead of regular mammalian scar tissue to heal injury. Blasterma is the structure associated with rapid cell growth and de-differentiation as seen in amphibians. It reacts more like stem cells rather than healing tissue, not leaving a trace of scar tissue. Imagine if we were able to actually harness this power to regrow limbs, fix destroyed body parts, etc. We're still a long way out from being able to apply this to ourselves, but its one of those things thats nice to think about. If you're into that sort of thing. If you are you might want to read the whole article.
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