Fig. 2

t(15;21)(q21;q22) translocation in cases 2, 3, and 4. a, b Breakpoints on chromosomes 21 and 15: partial karyotypes showing fluorescence in situ hybridization (FISH) results that allowed the mapping of t(15;21) translocation breakpoints on der(21) (a) and der(15) (b), using the consistently colored probes listed for cases 2 (first column) and 4 (second column). RP11-662O10 was used only in case 4. Cases 2 and 3 shared the same breakpoints (data not shown). On the right, the map of the BAC probes used in the FISH experiments, according to GRCh37/hg19, and identifying both translocation and deletion breakpoints, is shown. The black and orange dashed lines indicate the breakpoints in cases 2 and 4, respectively. The grey rectangle encompasses the deleted region flanking the translocation breakpoint in case 4. c Evaluation of RUNX1 and TCF12 expression levels: exon-specific reverse transcription quantitative polymerase chain reaction results of runt-related transcription factor 1 (RUNX1; left) and transcription factor 12 (TCF12; right) in case 2. Asterisks indicate statistically significant results (P < .05)