SCIENTISTS have created "miracle mice"
For starters, MRL mice are an inbred lab strain like many others so I would not try to rise the impression of a planned "creation". The researchers themselves prefer to call it "discovered by serendipity" ;-)
[1]The fact that they beleive that its almost certain that humans have the capabillity in our genes.
Once we can actually "create" these mice, i.e. turn the regeneration response on in non-regenerating donor mouse stem cells, we might consider that possibility again ;-) There are no naturally occuring "regenerator" humans known, are they?
When they injected fetal liver cells taken from those animals into ordinary mice, they too gained the power of regeneration.
In some, but not other tissues
[2]. This most likely reflects what type of stem cell participates in the regeneration of what tissue. I find this very interesting, perhaps one can one day make human applications of it. On the other hand, for the purpose of human rejuvenation therapy, one might alternatively want to regenerate our tissues from exogenous sources to fix all-types of age-related damage (see e.g. the infamous WILT). If one should end up choosing not delete telomere lengthening capability, but still to regenerate from exogenous sources (WILT "scaffold" without "proper"), then endogenous regeneration should make a cute addition. This gets us to your next question.
One thing that interests me would be, if we regrow an organ, would that organ have cells that are already aged.
Good thinking. As of today, there is no answer to that. If the organ came from few aged cells, then it would almost certainly carry some types of cell damage, but it these would almost certainly not be exactly the same types of cell damage that the organ would have if it had been around during all the time the cells have been around. We will know a bit more in a few months when the MRL longevity study comes to a close. My bet is they'll die from cancer (which is the usual cause of death of a lab mouse) perhaps slightly faster than others, but that's just a bet ;-)
Edited by John Schloendorn, 29 August 2005 - 10:42 AM.