One of the hallmarks of cancer is the occurrence of genetic instability. It drives the initiation and progression of tumor genesis (the emergence of a tumor) and frustrates effective therapy. Tumor cells display a wide array of derailments in genome control and repair systems, which allows tumors to rapidly acquire new properties. We aim to establish a comprehensive, systematic screening for genes that are implicated in genome stability. The mode of action of these genes will be examined at a molecular, cellular and organismal level. Knowledge of genome stability is highly relevant for the treatment of cancer and we expect this project to yield new critical targets for diagnosis and treatment and possibly novel etiological factors as well.