Patient-specific cells could be made without genetic manipulation. Scientists have demonstrated a new way to reprogram adult tissue to become cells as versatile as embryonic stem cells — without the addition of extra genes that could increase the risk of dangerous mutations or cancer. Researchers have been striving to achieve this since 2006, when the creation of so-called induced pluripotent (iPS) cells was first reported. Previously, they had managed to reduce the number of genes needed using small-molecule chemical compounds, but those attempts always required at least one gene, Oct42, 3. Now, writing in Science, researchers report success in creating...