Schematic representation of the 9p21 locus and its genomic alterations detected by a dedicated quantitative QMPSF assay in DLBCL. (A) The molecular organization of the locus is indicated. Abnormal copy numbers are represented by shaded rectangles (gray indicates heterozygous deletion; black, homozygous deletion). (B) Example of an electropherogram obtained with the dedicated 9p21 locus QMPSF assay. (C) Schematic repartition of the deletions involving the 9p21 locus.