Condensin complexes are essential for chromosome condensation and segregation in mitosis, while
condensin dysfunction, among other pathways leading to chromosomal bridging in mitosis, may play a role in
tumor genomic instability, including recently discovered chromotripsis. To characterize potential double-strand breaks specifically occurring in late anaphase, human chromosomes depleted of
condensin were analyzed by γ-H2AX ChIP followed by high-throughput sequencing (ChIP-seq). In
condensin-depleted cells, the nonrepeated parts of the genome were shown to contain distinct γ-H2AX enrichment zones 75% of which overlapped with known hemizygous deletions in
cancers. Furthermore, some tandemly repeated DNA sequences, analyzed separately from the rest of the genome, showed significant γ-H2AX enrichment in
condensin-depleted anaphases. The most commonly occurring targets of such enrichment included simple repeats, centromeric satellites, and
rDNA. The two latter categories indicate that acrocentric human chromosomes are especially susceptible to breaks upon
condensin deficiency. The genomic regions that are specifically destabilized upon
condensin dysfunction may constitute a
condensin-specific chromosome destabilization pattern.