Frequency of gene fusions detected in various types of leukemia using our targeted RNA-seq system. (A) Black bars indicate the frequency of gene fusions detected in patients with each leukemia type. Gene fusion was detected in 77% (72 patients) of all the 93 leukemia patients. Genetic fusion mutations were observed in 94% (33/35) of adult B-ALL patients and 83% (25/30) of pediatric B-ALL patients. (B) Gene fusion pattern and frequency for each type of leukemia. Among the gene fusions found in adult B-ALL (N=35), the most common fusion gene was BCR-ABL1 (24/33, 73%), and the most common fusion gene mutation in childhood B-ALL was ETV6-RUNX1 (4/26, 15%). Abbreviation: RNA-seq, RNA sequencing.