Structural variants and CNA formation in four regions on Chromosome 8. (A) Pictorial representation of the structural variants among the boundaries of four regions on Chromosome 8. (B) Heat map of CNA breakpoint junction distribution. The existence of four breakpoint junctions in 28 primary tumor cells, five CTCs, and three metastases from the colon cancer patient (Meta., metastases) was detected by PCR followed by next-generation sequencing. The primers were designed to target both sides of the breakpoint junction with appropriate orientation based on whole-genome sequencing. (C) A two-step model to elucidate the CNAs involving four regions on Chromosome 8 containing the MYC gene. Sequential FoSTeS events first caused the CNA regions to be duplicated, after which homologous recombination further amplified these duplicated regions to extreme copy numbers.
