Telomerase-independent telomere lengthening is a potential target for cancer therapy, but molecules specific to this pathway have remained elusive. Henson et al. show that DNA circles of (CCCTAA)_n are specific intermediates of alternative lengthening of telomeres and present a sensitive assay to detect them.

As the first commercial ventures are formed around induced pluripotent stem cells, who will have freedom to operate commercially remains an unknown.

Rapid clearance frequently complicates therapeutic use of proteins and peptides. Schellenberger et al. demonstrate that genetic fusion of an unstructured polypeptide offers a general strategy to extend peptide or protein half-life in vivo in a tunable manner.

With a flood of cancer genome sequences expected soon, distinguishing 'driver' from 'passenger' mutations will be an important task. Wang et al. describe a bioinformatic method for identifying cancer-associated fusions and apply it to discover a recurrent rearrangement in lung cancer.