Research Paper Volume 7, Issue 2 pp 110—122

Figure 4. DSB-related DDR. (A) H2AX phosphorylation was determined in dermal fibroblasts by immune blotting [46] without (open circles) and with (closed circles) pre-treatment with 50 μm VP16. Mean data of three independent cultures, SEM < 20% of the mean is omitted for the sake of clarity. (B) Cross-comparison of base line H2AX phosphorylation (in the absence of VP16, same data as represented by open symbols in section A of this figure) and frequency of structural chromosome aberrations (same data as shown in Fig. 3 D). (A, B) Results of linear regression are stated as R²: Pearson's coefficient for goodness of fit, p: probability for slope = 0, dotted lines: 95% confidence limits of linear regression, and N.S.: linear regression of the data revealed no significant age-related change in the parameters.