Reprogrammed mouse skin cells have resulted in living mice. Mice that have since reproduced and seen their offspring reproduce as well. "The reprogrammed adult cells, known as induced pluripotent stem cells or iPS cells" are similar to embryonic stem cells however researchers are unsure if these cells can produce any type of cell like that of embryonic cells or if they can simply reproduce many of the same cells.
The living mice are another step in the test to see if IPC's can be manipulated in the same way as embroyonic stems cells have. "This test is considered a gold standard of pluripotency: Because the original double-chromosomed cells are doomed, the embryo can only become an adult if the added stem cells turn into every necessary cell type. Embryonic stem cells passed this test a decade ago. Now iPS cells have, too."