Abstract
Populations belonging to the XO and neo-XY races of P. cucullata have been analysed with C-banding and fluorescent DNA-binding dyes. The extent of C-heterochromatin variation was found to be considerably greater than that described in previous papers. Most of the heterochromatinized regions are GC-rich and could be derived from the GC-rich sequences of the NORs. Since the gain of heterochromatin does not involve detectable modification of the chromosome size, the heterochromatinization process may be considered as an example of euchromatin transformation. On the other hand, the distribution of heterochromatin in the sex chromosomes seems to be markedly non-random, probably due to the selective advantage of a complementary distribution between neo-X and neo-Y chromosomes.
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Sentis, C., Fernandez-Piqueras, J. Nature and distribution of heterochromatinized regions in the chromosomal races of Pycnogaster cucullata (Insecta, Orthoptera). Genetica 72, 127–132 (1987). https://doi.org/10.1007/BF00123170
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DOI: https://doi.org/10.1007/BF00123170