MYC FISH patterns. Cells without a translocation exhibit 2 fusion signals indicative of 2 intact MYC loci (A). In MYC translocated cells, one of the fusion signals is typically split into separate red (centromeric) and green (telomeric) signals. The break-apart can also be accompanied by a gain of the red or green probe (B). So far, there has been uncertainty about the interpretation of unbalanced FISH patterns with loss of either the green or red probe (C). The current study by Collinge et al provides evidence that such alterations reflect genuine rearrangements rather than deletions of the MYC locus.