ABSTRACT
Gene fusions occur when two genes are joined in any of a number of ways. Most commonly this happens by physical rearrangement of a chromosome during a deletion, translocation, inversion, or duplication. Alternatively, these can occur when two genes are read in one transcription event. The pace of oncogenic fusion drug discovery has escalated. Non–small-cell lung cancer (NSCLC) in particular, has been a frequent benefactor of fusion directed therapy. Oncogenic fusions often lead to constitutively active transcription of a gene, which could be detected by measuring expression using RNA microarrays. These microarrays are high throughput and can measure thousands of RNA transcripts at once, making them ideal for discovery of new oncogenic gene fusions. The paradigm for detecting oncogenic fusions in the clinic is to move from specific to expansive, at least in select diseases. The most applicable is NSCLC where companion diagnostics for ALK and ROS1 are available.
