Are there different kinds of stems cells?
Yes. Stem cells come in three forms: embryonic stem cells, embryonic germ cells and adult stem cells. Embryonic stem cells come from embryos, embryonic germ cells from testes, and adult stem cells can come from bone marrow. Embryonic stem cells are pluripotent — they have the ability to become virtually any type of cell within the body. Adult stem cells are more limited. They are found in adult organs. They are still developing and they have the potential to become any of the major specialized cell types within that organ. But recent evidence suggests it may be possible to reprogram adult stems to repair tissues. In a study published in the online journal Nature on March 1, 2009, Canadian researches described a new method for generating stem cells from adult human tissue. The researchers, at Mount Sinai Hospital in Toronto, say the development could bring personalized regenerative medicine a step closer to reality. “This new method of generating stem cells does not require embryos as s