Landmark Paper Has an Image Problem

New questions about scientific validity are dogging South Korean cloning researcher Woo-Suk Hwang and his colleagues. On 4 December, Hwang notified Science editors that a figure in online material that accompanies his group's heralded 2005 paper on the derivation of stem cells from cloned human embryos contained duplicate images. The problem follows close on the heels of Hwang's admission that, despite his previous denials, two members of his lab had donated oocytes for his group's experiments and others had been paid for their donations (Science, 2 December, p. 1402).