Figure 4

Scheme illustrating gene amplification and heterogeinity driven by asymmetric chromosomal segregation during BFB-cycles. After an initial break uncapped chromosomes may fuse and form a bridge during anaphase. Breakage of this bridge will form two different daughter cells one with amplification and one with deletion of the marker gene (digits indicate gene copy numbers). As chromosomes remain uncapped recurrent cycles will promote amplification as well as heterogeneity of the cell population. By this cells with decreased, normal and increased gene copy numbers persist simultaneously within the cell population.