Pachytene chromomere maps of Chinese hamster autosomes

A standard chromomere map of the Chinese hamster autosomes at pachytene has been prepared and presented. Comparison of bands on somatic chromosomes and chromomeres on meiotic chromosomes revealed a close correspondence between the two. Chromosome contraction from prophase to metaphase at mitosis and early to late pachytene at meiosis lead, due to coalescence, to the recognition of decreasing numbers of bands and chromomeres. As expected, a greater number of chromomeres could be recognized at pachytene than could Giemsa- and Quinacrine-positive bands at somatic metaphase.