Puzzlenaut said:
You don't necessarily need a cell taken before puberty -- just a cell with telemeres long enough so that the DNA hasn't been significantly damaged.
It might require the sampling of tens of thousands of cells, but the chopping off of bits of DNA is a random process, and when there are 10 to the 14 cells in the body, odds are a few are still pretty much intact.
Fair point, though an option would be to treat extracted cells with TERT enzyme activators (i.e. get telomerase going), and while it's yet to be proven in humans (I think), it's still plausible, I guess. Anyway, I believe they've already identified the spinal stem cells as being the best for such 'purposes' since they're the ones with telomerases that are most active.
However, that's only part of the problem. Since the remainder of the DNA has undergone a lot of division/replication, and DNA polymerases aren't known for fidelity... though I might just be thinking of family Y here. So errors can become an issue once replication starts kicking off.
*shrug*
Off-topic: idiot moment just then, was seriously wondering what you meant by '10 to the 14 cells in the body' o_0'... oh yeah, 10[sup]14[/sup].