As compared with the genomes of cancers from other disciplines, OS genomes have a relatively high-level, homologous recombination-deficient signature (typically characteristic of BRCA1/2-deficient cancers), suggesting that poly ADP-ribose(adenosine diphosphate–ribose) polymerase (PARP) inhibitors, which are active in cancers associated with BRCA1/2 mutation, may have activity in OS [46,47]. The gene discussed is BRCA1; the disease is cancer.