Fig. 2: CA landscape of spontaneous micronucleated cells in near-diploid human cell lines.

a, CAs detected per cell (P values on the basis of Fisher’s exact test). NS, not significant. b, Reciprocal CAs between sister cells. Segment annotation: dashed lines indicate an SCE, and demarcate shared and reciprocal segments. Red ticks mark points of inferred complex CA formation. NA, not available. c, Mitotic history reconstruction for reciprocal CAs in b. Orange and teal colours correspond to Watson and Crick template-strand orientations, respectively. d,e, Breakdown of CA classes in micronucleated MCF10A (d) and RPE-1 (e) cells, class percentage over all CAs. See Methods for CA classification criteria. f,g, CA count per chromosome in micronucleated MCF10A (f) and RPE-1 (g) cells (binomial testing was used to identify enrichments). In RPE-1, the highest CA counts are seen for Chr. 10 and Chr.  X engaging in an unbalanced der(X) t(X;10) translocation—a derivative chromosome that could be particularly susceptible to inclusion in micronuclei—in this cell line²⁹. h, Scheme showing mitosis with a dicentric chromosome. Sister chromatid fusion generates a dicentric. During anaphase, the dicentric chromosome forms a bridge, which can rupture and potentially form micronuclei in daughter cells. i, Chromothripsis affecting Chr. 13, with reciprocal segment inheritance into sister cells seen for a large fraction of the affected homologue. Top, Strand-seq data. Bottom, smoothened, normalized read counts along chromosomal positions.