Evidence for sex microchromosomes in a species with temperature-influenced sex determination (Crotaphytus collaris)

Wiggins, J.; Santoyo-Brito, E.; Scales, J.; Fox, S.

doi:10.1101/270983

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bioRxiv · 10.1101/270983

Evidence for sex microchromosomes in a species with temperature-influenced sex determination (Crotaphytus collaris)

Wiggins, J.·Santoyo-Brito, E.·Scales, J.·Fox, S.

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Abstract

The characteristics of a species evolution can be powerfully influenced by its mode of sex determination and, indeed, sex determination mechanisms vary widely among eukaryotes. In non-avian reptiles, sex was long thought to be determined bimodally, either by temperature or genetics. Here we add to the growing evidence that sex determining mechanisms in reptiles fall along a continuum rather than existing as a mutually exclusive dichotomy. Using qPCR, we demonstrate that the lizard Crotaphytus collaris possesses sex-based gene dosage consistent with the presence of sex michrochromosomes, despite that extreme incubation temperatures can influence hatchling sex ratio. Our results suggest a temperature override that switches genotypic females to phenotypic males at high and low temperatures.

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Wiggins, J., Santoyo-Brito, E., Scales, J., Fox, S.. 2018-03-19. Evidence for sex microchromosomes in a species with temperature-influenced sex determination (Crotaphytus collaris). https://doi.org/10.1101/270983

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