C. Examples of metaphase spreads for non-treated (NT) clone 35 cells and clone 35 treated with 4-OHT for 4 and 7 days. White arrowheads indicate fragile telomeres, the red arrowhead indicates a sister-chromatid fusion. Scale bar equals 6 µm. D. Quantification of fragile telomeres (left graph), sister chromatid fusions (middle graph) and chromosome fusions (right graph) as a percentage of events per metaphase. Experiments were performed in triplicate. At least 25 metaphases were examined per condition per replicate. The mean is displayed and error bars represent ± SD. Significance was determined using one-way ANOVA. p-values are indicated on the graph. 