DSBs repair dynamics. A) Spermatocyte spread nuclei stained for γH2AX (blue), RAD51 (red) and SYCP3 (green). Single stainings are shown in gray scale. Percentages indicate the fraction of pachytene nuclei observed as shown. Zygotene nuclei were identified based on the fact that axes were split for more than one chromosome pair, and γH2AX and RAD51 staining signals were extensive. Pachytene nuclei were identified based on complete synapsis of the autosomes, and we discriminated between early-pachytene (γH2AX staining of the XY body, and still some RAD51 foci on autosomes), mid-pachytene (γH2AX staining of XY body but no RAD51 foci on autosomes), and late-pachytene (no γH2AX staining on the XY body, and thickened SYCP3 axes of the XY body) spermatocytes. Diplotene nuclei were characterized by desynapsis and thickening of the SYCP3 ends. Scale bar represents 10 μm. B) Spermatocyte spread nuclei stained for γH2AX (blue), RAD51 (green), SYCP1 (green), and SYCP3 (only shown in the enlargement, in grayscale). Close-ups show a magnification of the XY body, the top image shows SYCP3 staining (grayscale) in the area, for which the merge of SYCP1, RAD51 and γH2AX is shown below.