NPM1 and acute myeloid leukemia: In contrast, mutations in TP53, and in genes encoding for splicing factors (SF3B1, SRSF2, U2AF1, ZRSR2) were less common, likely reflecting differences in disease biology—e.g., high frequency of normal karyotypes and NPM1 mutations generally observed in FLT3-mutated AML—and age distribution (median age 47.9 years) compared to the median age of the general AML population of about 70 years [33].