In a previous study of T‐ALL, we evaluated fifteen cases in early childhood (age ≤24 months) for mutations that are prevalent in infant ALL (pro‐B) or T‐ALL; NOTCH1 mutations, although found less frequently than described for older T‐ALL paediatric cases, were the most frequent alterations among these younger patients, followed by the KMT2A‐r (Emerenciano et al, 2006; Mansur et al, 2010). The gene discussed is NOTCH1; the disease is acute lymphoblastic leukemia.