The Scientist looks at what can and can't be done with adult stem cells: "the scientific debate persists as to whether adult stem cells are multipotent, or if they even need to be in order to be therapeutically relevant. ... both authors came to similar conclusions about the implications of their findings. 'We both speculated that it may be serving a positive function in neurodegenerative disease, repairing tissues that are damaged,' says Blau, who notes that earlier studies in animals showed that tissue damage enhances bone marrow cell contribution. ... Wagers contends that even if bone marrow cells do in fact contribute to brain, the contribution is too low to be therapeutically beneficial. "But if you wanted to take an approach of trying to enhance that contribution, then it would be important to know the mechanism by which it was occurring.'"