Bally et al. found higher incidence of M3v in patients with APL aged < 18 ( 23% ≤12 y, 24% 13 to 18 y; 13 % 19 to 60 y; p=0.03) but no difference regarding PML/RARα isoforms (bcr1: 50% ≤12 y, 62% 13 to 18 y; 61 % 19 to 60 y; bcr2: 14% ≤12 y, 9% 13 to 18 y; 9 % 19 to 60 y; bcr3: 36 ≤12 y, 29% 13 to 18 y; 30% 19 to 60 y; p= 0.79).33 Similarly, M3v and the PML/RARα isoforms bcr2 and bcr3 were found not to be increased in the AIEOP-GIMEMA and PETHEMA studies when compared to adults. This evidence concerns the gene PML and acute promyelocytic leukemia.