Fig. 2: High SJ copy numbers at diagnosis correlate with subsequent relapse.
From: Excised DNA circles from V(D)J recombination promote relapsed leukaemia
a, Total IGK/IGL SJ levels were determined in samples from patients with BCP-ALL (from VIVO Biobank) at diagnosis using LAM-ESC. Normalized copy number of each SJ at diagnosis for patients who later relapsed (n = 34) and those who remained in remission (non-relapse; n = 37) are plotted. Normalized reads were calculated by dividing the reads obtained per SJ by the total LAM-ESC reads in that experiment. A threshold (horizontal line) was set at the highest normalized ESC level detected in healthy blood (HB, n = 2). SJ levels in a bone marrow sample taken at remission (REM) are shown for comparison. Only SJs resulting from deletional recombination events are shown. b, A significantly higher number of distinct SJs is present at levels above the threshold in patients who subsequently relapse compared with those who remain in remission. P value was determined by a two-tailed Fisher’s exact test. n = 34 (relapse) and 37 (non-relapse). c, Left, expression of RAG1 and RAG2 mRNA at diagnosis in patients who later relapsed (n = 5) and those who did not (n = 6); comparable RAG1 expression levels were observed in both groups. Right, normalized SJ copy numbers. The P value was determined by a two-tailed Fisher’s exact test.
