MLLT1 and acute myeloid leukemia: Pediatric AML patients (n = 465) displayed the following rearrangements: MLLT3 (n = 170; 36.6%), ELL (n = 32; 6.7%), MLLT10 (n = 109; 23.4%), AFDN (n = 42; 9.0%), MLLT1 (n = 28; 6.0%), KMT2A-PTD (n = 7; 1.5%), EPS15 (n = 5; 1.1%), AFF1 (n = 1; 0.2%) and 28 other KMT2A rearrangements.