Fig. 1

Sex chromosome chain conformation at late prophase I. Total testis cell suspensions were methanol:acetic acid fixed prior to serial BAC probe DNA FISH hybridisations. Dual colour DNA FISH signals were recorded prior to additional dual colour FISH experiments on the same slide. All signals are positioned within or immediately adjacent a DAPI intense heterochromatic mass. Bottom panel shows representative positions of collated signals from four experiments using eight different BAC probes linked by an arbitrarily drawn line. Schematic at bottom is of sex chromosome chain with corresponding positions of BAC probes. FISH fluorescence in situ hybridisation, DAPI 4’6-diamidino-2-phenylindole