HER2 -amplified pancreatic ductal adenocarcinoma. (A) Single nucleotide polymorphism (SNP) array showing amplification on chromosome 17 containing the HER2 locus (boxed). (B) Inverted amplification on chromosome 17, spanning HER2 and truncating MED1 and TOP2A at either end (chr17:37,565,271-38,554,848). (C) Circos plot showing mutations and structural rearrangements of patient 9 (Table 2). Genes with non-silent substitutions are shown on the outer wheel. The SNP array data are shown on the subsequent plots (copy number predictions and B-allele frequency of probes). Structural rearrangements are indicated with lines inside the circle: deletions (green), inversions (yellow), intra-chromosomal rearrangements (blue), foldback inversions (light orange), and amplified inversions (dark orange). Genes with structural variation are shown in blue if deleted and green if interrupted.