A ZZ/ZW microchromosome system in the spiny softshell turtle, Apalone spinifera, reveals an intriguing sex chromosome conservation in Trionychidae

@article{Badenhorst2013AZM,
  title={A ZZ/ZW microchromosome system in the spiny softshell turtle, Apalone spinifera, reveals an intriguing sex chromosome conservation in Trionychidae},
  author={Daleen Badenhorst and Roscoe Stanyon and Tag N. Engstrom and Nicole Valenzuela},
  journal={Chromosome Research},
  year={2013},
  volume={21},
  pages={137-147}
}
Reptiles display a wide diversity of sex-determining mechanisms ranging from temperature-dependent sex determination (TSD) to genotypic sex determination (GSD) with either male (XY) or female (ZW) heterogamety. Despite this astounding variability, the origin, structure, and evolution of sex chromosomes remain poorly understood. In turtles, TSD is purportedly ancestral while GSD arose multiple times independently. Here we test whether independent (XY or ZW) or morphologically divergent… 
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