Figure 1.

A–D) Frequency of histone H3PS10–positive cells in control and MCPH1 cells determined by flow cytometry after incubation with nocodazole alone (A) or combined with either ICRF-193 (B), caffeine (C), or both (D) for the indicated time points. Mean and range (bars) data from 2 independent experiments are presented. Pooled data from control and patient cells were compared by χ² test of independence. E–H) Fold increase of G₂ cell fraction, related to untreated samples, in control and MCPH1 cells incubated as described in A–D during 3 h (E), 6 h (F), 10 h (G), and 13 h (H). Mean and range (bars) data from 2 independent experiments are presented. For each time point, pooled data for each treatment were compared independently in control and patient cells by χ² test of independence to nocodazole-treated cells. Furthermore, for each treatment and time point, control and patient data were pairwise compared by χ² test of independence (underlined). CAFF, caffeine; NOC, nocodazole; ns, nonsignificant. *P < 0.01, **P < 0.001.