Abstract
The G- and C-banding patterns of mitotic chromosomes from four species of antelope squirrels (Ammospermophilus harrisi, interpres, leucurus and nelsoni) are discussed with special attention payed to the unusual quantities and position of constitutive heterochromatin. Heterochromatin appears to be responsible for the observation that cells from antelope squirrels contain over 70% more DNA than cells from another ground squirrel. A substantial fraction of this excess DNA consists of sequences that band as satellites in neutral CsCl or Cs2SO4-Ag+ density gradients. Interspecies similarities in the distribution of heterochromatin suggest that it has a function of some importance to these species and has therefore been conserved.
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Mascarello, J.T., Mazrimas, J.A. Chromosomes of antelope squirrels (genus Ammospermophilus): A systematic banding analysis of four species with unusual constitutive heterochromatin. Chromosoma 64, 207–217 (1977). https://doi.org/10.1007/BF00328078
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DOI: https://doi.org/10.1007/BF00328078