The News and Views article “Molecular biology: Complicity of gene and pseudogene” (Nature 423, 26–28; 200310.1038/423026a) discussed the discovery of pseudogene function in the mouse, as described by S. Hirotsune et al. on pages 91–96 of the same issue. There is an earlier report of pseudogene function, in a mollusc and with a different mechanism (S. A. Korneev, J.-H. Park & M. O'Shea J. Neurosci. 19, 7711–7720; 1999).