To study why the function of Pax5 may be impaired in Pax5Jak2/+ B‐ALL cells, we next compared the RNA‐seq expression pattern at the Pax5 locus in Pax5+/+ pro‐B cells and Pax5Jak2/+ B‐ALL tumors. The gene discussed is PAX5; the disease is acute lymphoblastic leukemia.