Abstract
The Siamese crocodile (Crocodylus siamensis), listed in CITES Appendix I, is considered one of the most critically endangered crocodilians in the world, and the reintroductions of it have been tried. Investigation of genetic variation for Siamese crocodile can help to conserve and improve this endangered species. Fourteen microsatellite loci were developed and twelve polymorphic loci were used to investigate the genetic variation and genetic bottleneck hypothesis on 48 captive individuals sampled in Guangdong Provincial Wildlife Rescue Center in Guangzhou. The allele number of polymorphic markers ranged from 2 to 10 per locus, with the average of 4.357. Observed heterozygosity ranged from 0.063 to 0.649 and expected values ranged from 0.259 to 0.844. The Shannon information index and Polymorphic Information Content showed that most of the loci were highly informative with an overall mean of 0.941 and 0.440, respectively. The bottleneck analysis provided evidence of a significant genetic signature of population decline.
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Acknowledgments
We acknowledge the financial support of the Natural Scientific Foundation of Guangdong Province (No. 9151026001000003), Excellent Young Scientist Foundation of Guangdong Academy of Sciences (No. 2008), Guangdong Provincial Public Laboratory on Wild Animal Conservation and Management (No. 2009).
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Yu, D., Peng, J., Hu, S. et al. Analysis of genetic variation and bottleneck in a captive population of Siamese crocodile using novel microsatellite loci. Conservation Genet Resour 3, 217–220 (2011). https://doi.org/10.1007/s12686-010-9326-y
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DOI: https://doi.org/10.1007/s12686-010-9326-y