Like the plastic aglets at the ends of shoelaces, telomeres normally protect the ends of chromosomes from instability and degradation – the hallmarks of cancer. Johns Hopkins University researchers recently revamped the model of how degradation happens. Previously, end-to-end chromosomal fusion events and breakage were regarded as the prime initiator, but new work reveals that exonucleases first chew away at chromosomes with short telomeres. Carol Greider, a Johns Hopkins professor, calls the result "a surprise."
Greider and graduate student Jennifer Hackett began work after observing in