In patient P-31, who developed a high-hyperdiploid BCP-ALL at the age of 2.5 years, it was caused by a PTPN11 (p.Asn308Asp) mutation and in Patient P-120, who developed ETV6::RUNX1-positive BCP-ALL when he was 1.7 years old, it resulted from an already previously reported Noonan-associated SOS1 (p.Phe868Leu) mutation (24, 25). The gene discussed is RUNX1; the disease is acute lymphoblastic leukemia.