Abstract: One embodiment provides methods to identify known and unknown gene fusions by creating a cDNA circle and analyzing the circle cDNA by amplification or sequencing. The circle cDNA is created in two approaches: 1) reverse transcribe a target RNA to cDNA, ligate the 3?end of the cDNA to its 5?end to form a circle cDNA, or 2). ligate the 3?end of target RNA to its 5? end to form a circle RNA, reverse transcribe the RNA to a cDNA, and ligate the cDNA to form a circle cDNA. The circle cDNA is amplified using a primer designed from a known sequence of a wild type target gene by rolling circle amplification or PCR methods. The known or unknown fusion gene sequences in the circle cDNA are amplified and identified by sequencing analysis.