Fig. 9.

Junction point sequencing highlights different mechanisms signatures. A Junction point from a translocation between chromosome 3 and chromosome X with insertion of nucleotides from Non-Homologous End-Joining (NHEJ) mechanism. At the top, the chromatogram displays chromosome 3 (underlined in pink) and chromosome X (underlined in blue). At the bottom, the alignment of the derivative (der) chromosome 3 (middle) with the reference sequence chromosomes 3 (pink) and X (blue). In red, four nucleotides were added for the ligation of the chromosomes by NHEJ. B Junction point from an inv dup del(13q) with microhomologies from the Fold-back mechanism. At the top, the chromatogram displays the spacer (underlined in pink) and the inverted duplication (underlined in blue). At the bottom, the alignment of the derivative chromosome 13 with the reference sequence of the spacer (pink) and the inverted duplication (blue). In purple, three nucleotides of the microhomology that prompted the Fold-back mechanism's occurrence. C Junction point from a complex rearrangement involving both arms of chromosome 18 with an insertion from a replication (FoSTeS/MMBIR) mechanism. At the top, the chromatogram displays the normal region of the long arm (underlined in pink), the inserted region of the long arm (underlined in green), and the inverted duplication of the short arm (underlined in blue). At the bottom, the alignment of the altered derivative 18 with the reference sequence of the long arm (pink), the insertion of the long arm (green), and the short arm (blue). In purple, four nucleotides of microhomology between the two regions of the long arm, and the two nucleotides of microhomology between the insertion and the short arm