Abstract Gene fusions play an important role in tumorigenesis and are increasingly recognized as important entities for the diagnosis and treatment of hematological malignancies and solid tumors. Fusion events generate a hybrid mRNA transcript comprising sequence from multiple otherwise distinct genes. Oncogenic fusion events often involve tyrosine kinases or transcription factors, leading to aberrant growth signaling, making these events potentially attractive drug targets. For instance, targeted therapies such as known tyrosine kinase inhibitors are currently approved to treat ALK fusion positive Non-Small Cell Lung Carcinoma (NSCLC) patients. Detection of known gene fusion events is an important part of genomic characterization which can inform patient diagnosis. Current methods for fusion detection include chromosome banding analysis (CBA), fluorescence in situ hybridization (FISH), and reverse transcription polymerase chain reaction (RT-PCR). New developments in next-generation sequencing (NGS) enable the efficient and simultaneous assessment of multiple gene fusion targets with high sensitivity. To enable researchers to design their own custom panels and assess a set of gene fusions of interest, we developed a comprehensive RNA gene fusion database. Oncology researchers now have the capability to create custom panels from this comprehensive database which includes over 1,000 well annotated and optimized gene fusion assays and over 20,000 gene expressions assays. To build this comprehensive gene fusion database, we identified breakpoint information for 1,178 well annotated fusions described in publications and in the COSMIC and NCBI databases. We prepared a target RNA sequence for each breakpoint using transcript sequences from the Ensembl database. We used a proprietary primer designer to generate candidates for each fusion target amenable to the AmpliSeq™ product line requirements. Quality control was performed throughout the design process to identify the best primer set for each target, to avoid primers overlapping common germline SNPs, potential primer/primer or primer/amplicon interactions, or off-target or wild-type amplifications. With this comprehensive database we provide a complete range of solutions available on ampliseq.com. Making use of the AmpliSeq™ technology, researchers now have the capability to create their own custom fusion panel and place the order within an hour. These custom panels are used with AmpliSeq™ Library reagents and Ion Torrent™ sequencing platforms for targeting next-generation sequencing. The analysis solution is provided through the Ion Reporter™ (IR) software package. Custom fusion panel workflows in IR are used to analyze sequencing data coming from the custom panels, which includes visualization of fusion transcripts and gene expression levels in a heat map feature. Citation Format: Efren Ballesteros-Villagrana, Jeoffrey Schageman, Kelli Bramlett, Paul Williams, Scott Myrand, Guoying Liu, Fiona Hyland, Seth Sadis. Gene fusion database to create custom panels: Enabling detection of fusion transcripts and gene expression assays. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5267.