PAX5 and acute lymphoblastic leukemia: To determine whether the wild‐type PAX5 allele is present or absent in human PAX5‐JAK2+ B‐ALL cells, we interrogated the RNA‐seq data of 8 human PAX5‐JAK2+ B‐ALL tumors to identify sequence reads spanning the unique exon junctions of the wild‐type PAX5 gene (exon 5‐exon 6) and PAX5‐JAK2 rearrangement (PAX5 exon 5‐JAK2 exon 19).