Please use this identifier to cite or link to this item:
|Scopus||Web of Science®||Altmetric|
|Title:||Sex determination in platypus and echidna: autosomal location of SOX3 confirms the absence of SRY from monotremes|
|Citation:||Chromosome Research, 2007; 15(8):949-959|
|Publisher:||Kluwer Academic Publ|
|M. C. Wallis, P. D. Waters, M. L. Delbridge, P. J. Kirby, A. J. Pask, F. Grützner, W. Rens, M. A. Ferguson-Smith, J. A. M. Graves|
|Abstract:||In eutherian (‘placental’) mammals, sex is determined by the presence or absence of the Y chromosome-borne gene SRY, which triggers testis determination. Marsupials also have a Y-borne SRY gene, implying that this mechanism is ancestral to therians, the SRY gene having diverged from its X-borne homologue SOX3 at least 180 million years ago. The rare exceptions have clearly lost and replaced the SRY mechanism recently. Other vertebrate classes have a variety of sex-determining mechanisms, but none shares the therian SRY-driven XX female:XY male system. In monotreme mammals (platypus and echidna), which branched from the therian lineage 210 million years ago, no orthologue of SRY has been found. In this study we show that its partner SOX3 is autosomal in platypus and echidna, mapping among human X chromosome orthologues to platypus chromosome 6, and to the homologous chromosome 16 in echidna. The autosomal localization of SOX3 in monotreme mammals, as well as non-mammal vertebrates, implies that SRY is absent in Prototheria and evolved later in the therian lineage 210–180 million years ago. Sex determination in platypus and echidna must therefore depend on another male-determining gene(s) on the Y chromosomes, or on the different dosage of a gene(s) on the X chromosomes.|
|Keywords:||Ornithorhynchus anatinus; platypus; sex determination; SOX3; SRY; Tachyglossus aculeatus|
|Appears in Collections:||Molecular and Biomedical Science publications|
Environment Institute Leaders publications
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.