Characterization of t(15;17) breakpoints within the PML and RARA loci. The location of breakpoints indicated by ▾ in the 14 patients (numbers correspond with UPNs in Tables 1 and 2) within the PML gene on chromosome 15 (A; bcr3 region and bcr1/2 region) and intron 2 of RARA on chromosome 17 (B) are shown. Breakpoint locations are numbered according to the following GenBank accession numbers: PML intron 6 (bcr 1), S57791; PML intron 3 (bcr 3), S51489; and RARA intron 2, AJ297538.²³