Scientists from the lab of Franz Klein from the Department of Chromosome Biology at the Max Perutz Labs, a joint venture of the University of Vienna and the Medical University of Vienna, have now discovered that cells sometimes liberate DNA fragments at sites of paired, or double, DSBs. Whilst this presents an obvious risk of germline mutations as a consequence of erroneous repair or of integration of fragments from elsewhere at break sites, it may also be a source of evolutionary diversity. The study is published as a research article in Nature.