Mature TCRγδ + PICALM::MLLT10 positive T‐ALL responds well to standard treatment, whereas TCR‐PICALM::MLLT10 positive T‐ALL has a strikingly inferior outcome [1], suggesting that an earlier stage of leukemia stem cells (LSCs) is insensitive and resistant to conventional therapy. The gene discussed is MLLT10; the disease is acute lymphoblastic leukemia.