Causing an adult cell to act like an embryonic stem cell. During development, as cells become more and more specialized, they gradually lose the ability to turn on the genes that allow embryonic stem cells to be so versatile. The silencing of these genes seems to be responsible for keeping specialized cells specialized and limiting the differentiation capacities of adult stem cells. By “reprogramming” adult stem cells so that they can turn on the genes that allow versatility, scientists hope to cause them to revert to a more flexible state. It is even possible that scientists could one day “reprogram” any cell, not only stem cells. However, research in this area is in the early stages and scientists may be many years away from making an adult cell as versatile as an embryonic stem cell.