Additional copies of CBX2 in the genomes of males of mammals lacking SRY, the Amami spiny rat (Tokudaia osimensis) and the Tokunoshima spiny rat (Tokudaia tokunoshimensis)

@article{Kuroiwa2011AdditionalCO,
  title={Additional copies of CBX2 in the genomes of males of mammals lacking SRY, the Amami spiny rat (Tokudaia osimensis) and the Tokunoshima spiny rat (Tokudaia tokunoshimensis)},
  author={A. Kuroiwa and S. Handa and Chi E. Nishiyama and Eriko Chiba and F. Yamada and S. Abe and Y. Matsuda},
  journal={Chromosome Research},
  year={2011},
  volume={19},
  pages={635-644}
}
Tokudaia osimensis (the Amami spiny rat) and Tokudaia tokunoshimensis (the Tokunoshima spiny rat) have a sex chromosome composition of XO/XO, no Y chromosome. The mammalian sex-determining gene, SRY, is also absent in these species, which indicates that these spiny rats exhibit a novel sex-determining mechanism that is independent of SRY. To identify a candidate gene that controls this mechanism, the copy numbers and chromosomal locations of 10 genes with important functions in gonadal… Expand
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