Sex chromosome evolution: platypus gene mapping suggests that part of the human X chromosome was originally autosomal.
Abstract
To investigate the evolution of the mammalian sex chromosomes, we have compared the gene content of the X chromosomes in the mammalian groups most distantly related to man (marsupials and monotremes). Previous work established that genes on the long arm of the human X chromosome are conserved on the X chromosomes in all mammals, revealing that this region was part of an ancient mammalian X chromosome. However, we now report that several genes located on the short arm of the human X chromosome are absent from the platypus X chromosome, as well as from the marsupial X chromosome. Because monotremes and marsupials diverged independently from eutherian mammals, this finding implies that the whole human X short arm region is a relatively recent addition to the X chromosome in eutherian mammals.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- December 1991
- DOI:
- 10.1073/pnas.88.24.11256
- Bibcode:
- 1991PNAS...8811256W