Conservation Genetics Resources

, Volume 9, Issue 4, pp 651–658 | Cite as

Development of sexing primers in Glyptemys insculpta and Apalone spinifera turtles uncovers an XX/XY sex-determining system in the critically-endangered bog turtle Glyptemys muhlenbergii

  • Robert LitermanEmail author
  • Srihari Radhakrishnan
  • Jeff Tamplin
  • Russell Burke
  • Cassie Dresser
  • Nicole Valenzuela
Methods and Resources Article


In species or developmental stages where the sex of an individual cannot be reliably identified through external morphology, molecular markers can provide a critical tool to study sex-specific traits that are elusive otherwise. Here we generated two sets of sex-diagnostic PCR primers for each of two focal turtle species with contrasting genotypic sex determination (GSD) systems: the wood turtle, Glyptemys insculpta (XX/XY), and the spiny softshell turtle, Apalone spinifera (ZZ/ZW). These markers identified males and females with 100% accuracy as validated with numerous individuals of known sex. Notably, one of the markers developed for G. insculpta permitted the successful diagnosis of individual sex in the critically-endangered bog turtle, Glyptemys muhlenbergii, also with 100% accuracy. This cross-species application provided the first evidence that G. muhlenbergii shares an XX/XY sex-determining mechanism with G. insculpta, a finding with important evolutionary and conservation implications. Similarly, the markers from A. spinifera were successful in identifying the sex of two individuals (one male and one female) of the Chinese softshell turtle, Pelodiscus sinensis (ZZ/ZW). These cross-species observations highlight the potential applicability of these types of markers on closely related taxa that share a sex-determining mechanism, which should be tested in a case-by-case basis.


Endangered turtle conservation GSD Heterogamety Molecular sexing Next generation sequencing DNA-Seq Sex chromosome evolution Sex diagnosis XX/XY and ZZ/ZW genotypic sex determination 



This work was funded in part by a Bern W. Tryon Bog Fund Grant from the Knoxville Zoological Gardens to NV and RB, and National Science Foundation grant MCB 1244355 to NV. We greatly appreciate the assistance of Mike Ogle at Zoo Knoxville, Amanda Guthrie at the Virginia Zoo, and Steve DeSimone at Cold Spring Harbor Fish Hatchery and Aquarium for their assistance in this Project.

Supplementary material

12686_2017_711_MOESM1_ESM.docx (28 kb)
Supplementary material 1 (DOCX 28 KB)
12686_2017_711_MOESM2_ESM.docx (14 kb)
Supplementary material 2 (DOCX 13 KB)


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Copyright information

© Springer Science+Business Media Dordrecht 2017

Authors and Affiliations

  1. 1.Department of Ecology, Evolution, and Organismal BiologyIowa State UniversityAmesUSA
  2. 2.Department of BiologyUniversity of Northern IowaCedar FallsUSA
  3. 3.Department of BiologyHofstra UniversityHempsteadUSA
  4. 4.Department of Ecology and Evolutionary BiologyUniversity of Tennessee KnoxvilleKnoxvilleUSA

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