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Characterizing the chromosomes of the platypus (Ornithorhynchus anatinus)

Abstract

Like the unique platypus itself, the platypus genome is extraordinary because of its complex sex chromosome system, and is controversial because of difficulties in identification of small autosomes and sex chromosomes. A 6-fold shotgun sequence of the platypus genome is now available and is being assembled with the help of physical mapping. It is therefore essential to characterize the chromosomes and resolve the ambiguities and inconsistencies in identifying autosomes and sex chromosomes. We have used chromosome paints and DAPI banding to identify and classify pairs of autosomes and sex chromosomes. We have established an agreed nomenclature and identified anchor BAC clones for each chromosome that will ensure unambiguous gene localizations.

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Author information

Correspondence to Jennifer A. Marshall Graves.

Additional information

Daniel McMillan, Pat Miethke and Amber E. Alsop contributed equally to the work.

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McMillan, D., Miethke, P., Alsop, A.E. et al. Characterizing the chromosomes of the platypus (Ornithorhynchus anatinus). Chromosome Res 15, 961 (2007). https://doi.org/10.1007/s10577-007-1186-2

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Key words

  • chromosome painting
  • karyology
  • Ornithorhynchus anatinus
  • platypus
  • sex chromosomes