To test whether a PDX model could be used to predict patient relapse, the main study was conducted using 30 MR BCP-ALL patients selected from the ANZCHOG ALL8 trial (Supplementary Fig. S2).7 Only patients with high numbers of bio-banked vials were used, resulting inadvertently in a higher proportion of patients with NCI (National Cancer Institute) high-risk characteristics (>10 years old or white cell counts > 50). The gene discussed is OPN1SW; the disease is acute lymphoblastic leukemia.