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Title: Sexual dimorphism in the meiotic requirement for PRDM9: A mammalian evolutionary safeguard
In many mammals, genomic sites for recombination are determined by the histone methyltransferase PRMD9. Some mouse strains lacking PRDM9 are infertile, but instances of fertility or semifertility in the absence of PRDM9 have been reported in mice, canines, and a human female. Such findings raise the question of how the loss of PRDM9 is circumvented to maintain fertility. We show that genetic background and sex-specific modifiers can obviate the requirement for PRDM9 in mice. Specifically, the meiotic DNA damage checkpoint protein CHK2 acts as a modifier allowing female-specific fertility in the absence of PRDM9. We also report that, in the absence of PRDM9, a PRDM9-independent recombination system is compatible with female meiosis and fertility, suggesting sex-specific regulation of meiotic recombination, a finding with implications for speciation.  more » « less
Award ID(s):
1942620
PAR ID:
10206887
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
43
ISSN:
2375-2548
Page Range / eLocation ID:
eabb6606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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