Giemsa banding of meiotic chromosomes

Applying a Giemsa staining technique to the meiotic chromosomes of Anemone blanda demonstrates that Giemsa bands similar to those seen in the mitotic chromosomes are discernible at all the principal stages of meiosis. The bands are not a product of the Giemsa procedure since they can be seen in unstained preparations using phase-contrast optics as chromocentres in interphase nuclei and as condensed regions in prophase chromosomes. That the bands seem to be permanent features of the nucleus, whether it is dividing or otherwise is an important consideration for understanding their nature and function. Bands and chiasmata do not coincide indicating on the one hand that chiasmata are not responsible for differences in banding patterns and on the other hand that the conservation of bands is an indication that they are either inert regions or specialised regions with considerable adaptive significance. These alternatives can only be resolved by genetical studies of the banding phenomena.