Inability to detect exons 3, 4, and 5 from patient #54.

Shown is an ethidium-bromide–stained agarose gel demonstrating PCRs from cDNA of 5 AML patients amplifying the full-length wild-type sequence of PU.1 (1051 bp). In patient #54 (lane 3), only the splice variant involving exons 1 and 2 is detectable (335 bp). C indicates PU.1 wild-type plasmid serves as a positive control. H, water as a negative control.