, Volume 99, Issue 1, pp 83–86 | Cite as

Loop size in newt lampbrush chromosomes

  • Pedro León
  • James Kezer


Lampbrush chromosome 11 from the newtTaricha granulosa was studied by scanning electron microscopy (SEM) to determine the size of all loops in this bivalent. Measurements with an XY digitizer revealed a mean loop length of 14.9 µm, with a large standard deviation and a skewed distribution toward higher values. The size of the loops at this stage of diplotene extension is similar to that reported in other eukaryotes studies with different approaches. We estimated, from the DNA content of chromosome 11, that between 0.4% and 2.2% of the DNA is found in the loops while the rest of the DNA must remain in the compact chromomeres.


Standard Deviation Electron Microscopy Scanning Electron Microscopy Developmental Biology Skewed Distribution 
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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • Pedro León
    • 1
  • James Kezer
    • 2
  1. 1.Centro de Investigación en Biología Celular y Molecular (CIBCM) and School of MedicineUniversity of Costa RicaSan JoséCosta Rica
  2. 2.Department of BiologyUniversity of OregonEugeneUSA

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