Dataset Information

Genetic conflict outweighs heterogametic incompatibility in the mouse hybrid zone?

ABSTRACT:

Background

The Mus musculus musculus/M. m. domesticus contact zone in Europe is characterised by sharp frequency discontinuities for sex chromosome markers at the centre of wider clines in allozyme frequencies.

Results

We identify a triangular area (approximately 330 km2) where the musculus Y chromosome introgresses across this front for up to 22 km into domesticus territory. Introgression of the Y chromosome is accompanied by a perturbation of the census sex ratio: the sex ratio is significantly female biased in musculus localities and domesticus localities lacking Y chromosome introgression. In contrast, where the musculus Y is detected in domesticus localities, the sex ratio is close to parity, and significantly different from both classes of female biased localities. The geographic position of an abrupt cline in an X chromosome marker, and autosomal clines centred on the same position, seem unaffected by the musculus Y introgression.

Conclusion

We conclude that sex ratio distortion is playing a role in the geographic separation of speciation genes in this section of the mouse hybrid zone. We suggest that clines for genes involved in sex-ratio distortion have escaped from the centre of the mouse hybrid zone, causing a decay in the barrier to gene flow between the two house mouse taxa.

SUBMITTER: Macholan M

PROVIDER: S-EPMC2576241 | biostudies-literature | 2008 Oct

REPOSITORIES: biostudies-literature

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Genetic conflict outweighs heterogametic incompatibility in the mouse hybrid zone?

Macholán Milos M Baird Stuart J E SJ Munclinger Pavel P Dufková Petra P Bímová Barbora B Piálek Jaroslav J

BMC evolutionary biology 20081003

<h4>Background</h4>The Mus musculus musculus/M. m. domesticus contact zone in Europe is characterised by sharp frequency discontinuities for sex chromosome markers at the centre of wider clines in allozyme frequencies.<h4>Results</h4>We identify a triangular area (approximately 330 km2) where the musculus Y chromosome introgresses across this front for up to 22 km into domesticus territory. Introgression of the Y chromosome is accompanied by a perturbation of the census sex ratio: the sex ratio ...[more]

PMID: 18834509

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Dataset Information

Genetic conflict outweighs heterogametic incompatibility in the mouse hybrid zone?

Background

Results

Conclusion

Publications

Genetic conflict outweighs heterogametic incompatibility in the mouse hybrid zone?

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