The PML-RARA fusion is not detectable in historical blood samples of acute promyelocytic leukaemia patients.

Dear Editor, Acute promyelocytic leukaemia (APL) is characterized by the presence of the t(15;17) chromosomal translocation that generates the I PML-RARA i fusion gene [[1]]. To determine the sensitivity for detecting each breakpoint by PCR, leukaemic DNA samples were suspended at 20 ng/ L and iteratively diluted tenfold to a dilution of 1:10,000 into equimolar (20 ng/ L) pooled normal blood DNA from 10 healthy subjects. Here, to investigate whether I PML-RARA i is detectable in the blood before APL onset, we study four APL cases with blood DNA available, from the same individual, 2-12 years before diagnosis. [Extracted from the article]