Although the DNA methylation subgroups correlate with known prognostic factors in JMML (i.e., age at diagnosis, platelet count, genotype, and elevated HbF levels)2,15,42, only the methylation subgroup and, to a lesser extent, the presence of a somatic PTPN11 mutation were significant predictors for risk of relapse in a multivariate Cox-regression model. The gene discussed is PTPN11; the disease is juvenile myelomonocytic leukemia.