Genome sizes of the planarians D. lugubris (2n=8), D. polychroa (2n=8) and D. benazzii (2n=16) were evaluated on metaphase plates by measuring both the Feulgen-DNA contents and the karyotype lengths. In the three species, genome sizes are significantly different; this finding rules out the possibility of a karyotype evolution through simple chromosome rearrangements between D. lugubris and D. polychroa. A different Feulgen-DNA content per unit length of karyotype in the three species studied was also found, which suggests that DNA could be differently packed along metaphase chromosomes.
- genome size
- karyotype length
- nuclear DNA amount
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)