A rare exception to Haldane's rule: are X chromosomes key to hybrid incompatibilities?
Abstract
The prevalence of Haldane’s rule suggests that sex chromosomes commonly have a key role in reproductive barriers and speciation. However, the majority of research on Haldane’s rule has been conducted in species with conventional sex determination systems (XY and ZW) and exceptions to the rule have been understudied. Here we test the role of X-linked incompatibilities in a rare exception to Haldane’s rule for female sterility in field cricket sister species (Teleogryllus oceanicus and T. commodus). Both have an XO sex determination system. Using three generations of crosses, we introgressed X chromosomes from each species onto different, mixed genomic backgrounds to test predictions about the fertility and viability of each cross type. We predicted that females with two different species X chromosomes would suffer reduced fertility and viability compared with females with two parental X chromosomes. However, we found no strong support for such X-linked incompatibilities. Our results preclude X–X incompatibilities and instead support an interchromosomal epistatic basis to hybrid female sterility. We discuss the broader implications of these findings, principally whether deviations from Haldane’s rule might be more prevalent in species without dimorphic sex chromosomes.
Citation
Moran , P , Ritchie , M G & Bailey , N W 2017 , ' A rare exception to Haldane's rule: are X chromosomes key to hybrid incompatibilities? ' , Heredity , vol. 118 , no. 6 , pp. 554-562 . https://doi.org/10.1038/hdy.2016.127
Publication
Heredity
Status
Peer reviewed
ISSN
0018-067XType
Journal article
Rights
© 2017, Macmillan Publishers Ltd, part of Springer Nature. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at www.nature.com / https://doi.org/10.1038/hdy.2016.127
Description
This work was funded by NERC (NE/G014906/1, NE/L011255/1, NE/I027800/1). Additional funding from the Orthopterists’ Society to PM is also gratefully acknowledged.Collections
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