We examined transferrin receptor (TfR) 1 and TfR2 mRNA expression in 50 acute myeloid leukemia (AML) patients by RT-PCR, with primers specific for exons 15-17 (TfR1), 3-5 (TfR2-alpha) and 4-5 (TfR2-beta) of the corresponding gene. There were 4/50 TfR1-negative (-), 3/50 TfR2-alpha mRNA (-) and 13/50 TfR2-beta mRNA (-) cases; only three cases were TfR1/2 mRNA (-). No significant correlations were identified between TfR2-beta mRNA negativity and specific FAB subtypes, karyotype or attainment of complete remission. These findings suggest that: (i) TfR2 expression is not restricted to erythroid cells, and (ii) iron import proteins might complement each other in AML cells.