Fig. 5. FISH analysis of Atmnd1 mutants reveals defects in pairing and chromosome disjunction. Preparations of wild-type (A-C) and Atmnd1 (D-F) meiocytes were hybridised with FISH probes directed against an interstitial region of chromosome 1 (BAC F1N21, green) and a sub-telomeric region of chromosome 2 (BAC F11L15, red). (A,D) Zygotene stage, showing consistent association of sub-telomeric regions in wild-type and occasional association in Atmnd1 cells. (B) Wild-type pachytene/diplotene transition with paired FISH probes. (E) Atmnd1 pachytene-like stage with unpaired FISH signals. (C,F) Anaphase I with a regular distribution of chromosomes and FISH signals in wild-type meiocytes, as opposed to the irregular chromosome disjunction and DNA fragmentation in Atmnd1 cells. Chromosomes are stained with DAPI. Bar, 10 µm.