Cohybridization FISH experiments used to characterize hsr insertion sites. MYCN was used in all experiments to mark the hsr, and it was cohybridized with contiguous probes flanking the insertion (a,f) or with clones yielding split signals (b–e). (a) In STA-NB-3, the insertion is within the short arm of chromosome 13, between the centromere (alphoid probe, red) and the NOR region (RP5-1174A5). (c) In STA-NB-15, the BAC RP11-449J21 (red) displayed signals distally, proximally, and within the hsr (arrowheads), likely due to a duplication event occurring simultaneously to the hsr insertion process. (e,f) Cell line GLC14 showed two insertion sites. Map positions of all the clones are reported in Supplemental Table 1.
