
Cover The illustration symbolically shows the inexorable march of mammalian comparative genomics and heretofore hidden synteny relationships for human chromosome 11 on a backdrop of decondensed genomic DNA. Conserved cattle and mouse chromosome segments are overlaid on human chromosome 11 and their corresponding positions on the cattle and mouse chromosomes delineated. The conservation of segment boundaries in the three species supports a new hypothesis for mammalian chromosome evolution. (Cover designed by Nadia Ruvinskaya. [For details see Larkin et al., pp. 1966–1972.])