Table 1.

Monitoring DNA repair protein foci in fibroblasts with RNF168 deficiency.

Fibroblast line	Mean foci per cell			Percentage of foci-positive cells
	53BP1	γH2AX	p(γH2AX)	53BP1	γH2AX	p(γH2AX)a
ADP reference
1 h after 6 Gy	11 ± 3	43 ± 5	Ref	28 ± 1	67 ± 1	Ref
24 h after 6 Gy	3 ± 0	6 ± 2	Ref	18 ± 1	39 ± 8	Ref
48 h after 6 Gy	2 ± 0	3 ± 4	Ref	9 ± 1	13 ± 1	Ref
72 h after 6 Gy	1 ± 0	2 ± 2	Ref	7 ± 1	2 ± 1	Ref
F591 RNF168 deficient
1 h after 6 Gy	0	44 ± 1	0.80	0	71 ± 0	0.01
24 h after 6 Gy	0	13 ± 2	0.08	0	58 ± 1	0.07
48 h after 6 Gy	0	11 ± 3	0.12	0	45 ± 2	0.002
72 h after 6 Gy	0	9 ± 1	0.05	0	39 ± 1	0.0009
F592 RNF168 deficient
1 h after 6 Gy	0	52 ± 1	0.13	0	71 ± 2	0.12
24 h after 6 Gy	0	12 ± 1	0.06	0	61 ± 1	0.06
48 h after 6 Gy	0	11 ± 3	0.12	0	59 ± 2	0.001
72 h after 6 Gy	0	9 ± 0	0.04	0	43 ± 1	0.0007

The number of 53BP1 or γH2AX foci per cell and the percentage of foci-positive cells were assessed in primary fibroblasts from the two patients with RIDDLE syndrome (F591, F592) and wild-type fibroblasts from a healthy donor (ADP) at five time-points (0, 1, 24, 48, 72 h). Shown are the mean values from two technical replicates after normalization to the untreated condition (t = 0). Because no 53BP1 foci were detected in F591 and F592, the monitoring over time was only performed for γH2AX foci and p-values were determined by two-sample t-tests using ADP as the reference.

^ap < 0.01 marked in bold.