On the cover, a ribbon representation of the BRCA1/BARD1 RING domain heterodimer. Critical Zn2⁺-liganding cysteine residues in the BRCA1 RING domain (yellow are known sites of cancer-predisposing mutations. Mutation of these residues causes a local structural change in a surface-exposed loop (red). Superimposed is a pedigree for a family harboring a Cys-61--> Gly mutation. Filled yellow circles represent individuals diagnosed with breast or ovarian cancer. For details, see the article by Brzovic et al., pages 41399-41406.41399.