This volume is dedicated to Ulrich Wolf on the occasion of his retirement by his friends and associates
Editors: Michael Schmid, Würzburg; Harold P. Klinger, New York, N.Y.

Paper

The minimal mammalian Y chromosome - the marsupial Y as a model system
R. Toder, M.J. Wakefield, J.A.M. Graves

Department of Genetics, La Trobe University, Bundoora, Melbourne, Victoria (Australia)

Address of Corresponding Author

Cytogenet Cell Genet 2000;91:285-292 (DOI: 10.1159/000056858)

  Abstract.

The mammalian X and Y chromosomes are very different in size and gene content. The Y chromosome is much smaller than the X and consists largely of highly repeated non-coding DNA, containing few active genes. The 65-Mb human Y is homologous to the X over two small pseudoautosomal regions which together contain 13 active genes. The heterochromatic distal half of the human Yq is entirely composed of highly repeated non-coding DNA, and even the euchromatic portion of the differential region is largely composed of non-coding repeated sequences, amongst which about 30 active genes are located. The basic marsupial Y chromosome (about 10 Mb) is much smaller than that of humans or other eutherian mammals. It appears to include no PAR, since it does not undergo homologous pairing, synaptonemal complex formation or recombination with the X. We show here that the tiny dunnart Y chromosome does not share cytogenetically detectable sequences with any other chromosome, suggesting that it contains many fewer repetitive DNA sequences than the human or mouse Y chromosomes. However, it shares several genes with the human and/or mouse Y chromosome, including the sex determining gene SRY and the candidate spermatogenesis gene RBMY, implying that the marsupial and eutherian Y are monophyletic. This minimal mammalian Y chromosome might provide a good model Y in which to hunt for new mammalian Y specific genes.   

Copyright © 2001 S. Karger AG, Basel

  Author Contacts

Request reprints from Roland Toder at his current address:GeneScan Europe AG, Engesserstr. 4b, D-79108 Freiburg (Germany);telephone: 0049-761-5038 100; fax: 0049-761-5038111;email: rtoder@biochip.com

  Article Information

Supported by the Australian Research Council and GeneScan Europe AG.

Received: Received 1 August 2000;
manuscript accepted 18 September 2000.
Number of Print Pages : 8
Number of Figures : 3, Number of Tables : 0, Number of References : 58