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Dicentric chromosomes have been shown to be unstable because the two centromeres are prone to being pulled into different daughter cells during mitosis[37], and studies inS. cerevisiaehave provided insights into the fate of dicentric chromosomes. Engineered dicentric chromosomes have been shown to delete a centromere by HR between repeated sequences or by breakage and end-joining mediated deletion or alternatively such broken dicentric chromosomes can be healed by circularization, acquisition of a telomere or HR with another chromosome[38]–[41]. It has also been shown that the presence of inverted Ty elements or engineered inverted repeats can induce chromosome breakage resulting in a capped broken chromosome that can replicate to produce a dicentric chromosome much like a dicentric isoduplication[33],[35]. These dicentric chromosomes and dicentric chromosomes resulting from telomere-telomere fusion have been shown to break and be stabilized by either acquisition of a telomere[39],[40]or break induced replication (BIR) with another chromosome near Ty or delta elements resulting in a monocentric GCR[33],[36],[41]. Here we have analyzed the structure of spontaneous chromosome rearrangements isolated in different haploid telomerase deficient mutant backgrounds that were predicted to be dicentric GCRs based on the sequence of their primary translocation breakpoint[28],[30]. We found that all of the predicted dicentric GCRs were unstable and had undergone secondary rearrangements by a diversity of NHEJ- or HR-mediated events resulting in stable monocentric chromosomes; however, HR mediated events were found to predominantly contribute to the resolution of dicentric GCRs regardless of the primary rearrangement structure.