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While the basic side of stem cell research is prospering, several talks on translating research to therapy were sobering reminders of the challenges ahead.
That the depletion of stem cells as we age may be a consequence of DNA damage has been hinted at. New studies now show that DNA repair is needed to keep our blood stem cells in good working order as we age.
Dolly the sheep came not from the union of sperm and egg but from the mammary cell of one sheep and the unfertilized egg of another. Her birth, more than 10 years ago showed that nuclei from specialized adult cells can be reprogrammed into all the cells of an organism.
Much of the work that had previously convinced scientists that only oocytes, and not zygotes, could be used for cloning came from very careful studies by McGrath and Solter in the 1980s1,2. A few weeks before Kevin Eggan's paper3 was made public, Nature Reports Stem Cells tracked down Davor Solter to learn his thoughts.
Unfertilized eggs have long been the limiting resource for attempts to make genetically tailored human embryonic stem cells. If a new technique for cloning mice from fertilized eggs works in humans, they might not be necessary.