Isolation And Characterization Of Microsatellite Marker In The Chinese Crocodile Lizard (Shinisaurus Crocodilurus) And Analysis Of Genetic Structure

The Chinese crocodile lizard (Shinisaurus crocodilurus) is one of the critically endangered species in the world, and has been listed on Appendix Ⅱ of CITES. Because of poaching and habitat deterioration, the population of the Chinese crocodile lizard has drastically declined, to less than one thousand individuals. Crocodile lizards are mainly distributed with isolated populations in Guangxi and Guangdong of China and Vietnam. The Chinese crocodile lizard is already in urgent need of research and protection. Population genetics study on the Chinese crocodile lizard is relatively less, and microsatellite markers are an ideal tool for conservation genetic study. Therefore, the development of polymorphic microsatellite markers would be useful in studying population structure, mating system and parentage relationship of crocodile lizards. We report the isolation and characterization of12microsatellite loci in the Chinese crocodile lizard. The results are as follows:1. Twelve polymorphic microsatellites loci from Crocodile lizards were isolated as the enrichment by magnetic beads.2. A total of178distinct alleles were observed. The twelve loci were highly polymorphic with numbers of alleles per locus ranging from11to20with an average of14.8. Range of observed heterozygosity (Ho) was from0.8500to0.9750and that of expected heterozygosity (HE) was from0.8372to0.9347. The mean expected heterozygosity and observed heterozygosity of these microsatellites were0.9069and0.9490, respectively.3. All loci followed Hardy-Weinberg equilibrium (HWE) after Bonferroni correction. No evidence of significant linkage disequilibrium (LD) was found among any loci.4. The PIC values ranged from0.819to0.931with average value of0.886among these loci, the result show that the twelve microsatellite loci are highly polymorphic. Thus, the twelve novel polymorphic microsatellite loci will be useful for conservation genetic study in this species.5. The result indicate that the microsatellite can be used on studying population structure, mating system and parentage relationship of crocodile lizards, which will play an important role in the study of the population genetics and conservation genetics in the Chinese crocodile lizard. It also proved that noninvasive sampling is an availability sampling method for conservation genetics of the Chinese crocodile lizard.