Via EurekAlert!: "researchers describe how they are able to reprogram human adult skin cells into other cell types in order to decipher the elusive mechanisms underlying reprogramming. To demonstrate their point, they transformed human skin cells into mouse muscle cells and vice versa. This research shows that by understanding the regulation of cell specialization it may be possible to convert one cell type into another, eventually bypassing stem cells. ... Regenerative medicine provides hope of novel and powerful treatments for many diseases, but depends on the availability of cells with specific characteristics to replace those that are lost or dysfunctional. We show here that mature cells can be directly reprogrammed to generate those necessary cells, providing another way besides embryonic stem cells or induced pluripotent stem cells of overcoming this important bottleneck to restoring tissue function. ... Reprogramming mature cells will likely complement the use of embryonic stem cells in regenerating tissues. By elucidating the regulators of reprogramming [it] may be possible to generate replacement cells in cases where stem cells are not present or not appropriate."