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Title: XY sex determination in a cnidarian
Abstract Background Sex determination occurs across animal species, but most of our knowledge about its mechanisms comes from only a handful of bilaterian taxa. This limits our ability to infer the evolutionary history of sex determination within animals. Results In this study, we generated a linkage map of the genome of the colonial cnidarian Hydractinia symbiolongicarpus and used it to demonstrate that this species has an XX/XY sex determination system. We demonstrate that the X and Y chromosomes have pseudoautosomal and non-recombining regions. We then use the linkage map and a method based on the depth of sequencing coverage to identify genes encoded in the non-recombining region and show that many of them have male gonad-specific expression. In addition, we demonstrate that recombination rates are enhanced in the female genome and that the haploid chromosome number in Hydractinia is n  = 15. Conclusions These findings establish Hydractinia as a tractable non-bilaterian model system for the study of sex determination and the evolution of sex chromosomes.  more » « less
Award ID(s):
1923259
PAR ID:
10440481
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Date Published:
Journal Name:
BMC Biology
Volume:
21
Issue:
1
ISSN:
1741-7007
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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