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Not so long ago, researchers at the Wistar Institute in Philadelphia made a serendipitous discovery: when they punched identification holes in the ears of a certain strain of mice known as MRL, the holes rapidly healed without any sign of scar tissue, and with regenerated cartilage and hair follicles. Their curiosity was understandably piqued.
Further experiments showed that the regenerative potential of these mice was not limited to healing their ears. Researchers performed a series of experiments, surgically removing such things as toes, tails, and sections of heart from the mice, and each removed section grew back without evidence of scarring, joints and all. Of each surgically removed portion, only the brain tissue of the mice was unable to regenerate. The unique regenerative power of these mice is unheard of in adult mammals, but it is strikingly similar to that exhibited by some amphibians. Rather than regrowing damaged or lost tissues, mammal physiology closes the wound with scar tissue, which is the body’s quick response to prevent infection.
When cells from one of these regenerating mice is injected into an ordinary mouse, it takes on the ability to regenerate as well. After six months of observing these previously ordinary mice, there was no noticeable decline in this healing ability. The ability seems to be controlled by about a dozen genes, and researchers are almost certain that humans have comparable genes.
Naturally the military is interested in applying this technology to humans, as it would allow a wounded soldier to recover fully, including any amputated limbs or damaged organs. It also has some interesting implications in repairing non-genetic birth defects, since a defective limb or organ could be removed, and grow back normally. Scientists also believe that these extraordinary healing properties may extend the lifespan of an organism, but these mice are only eighteen months into their normal two-year lifespan, so it is too early to make any conclusions.
The potential for this regenerative ability in humans is extraordinary, but it is only a matter of time until the lawsuits from prosthetic limb manufacturers start up. Damn human nature.