DNA damage can also occur when cells have difficulties copying their DNA leaving it vulnerable to breakage. BRCA1 helps protect DNA when the copying machinery gets stuck, but it was not known how. Now University of Birmingham researchers, in collaboration with scientists at Imperial College London, have found that BRCA1 changes shape in order to protect vulnerable DNA until the copying machinery can be restarted. In addition, the researchers found that in some patients with a personal or family history of breast and ovarian cancer, the protective role of BRCA1 in DNA-copying is disabled - while its break repair function is still active.