Isolation and characterization of tetranucleotide repeat polymorphic microsatellite loci in Larus saundersi (Aves, Laridae).

Nine polymorphic microsatellite loci were isolated, using tetranucleotide repeat oligonucleotide probes from an enriched DNA library of the globally "vulnerable" Saunders's gull (Larus saundersi), collected from the Yancheng coastal wetland, one of the three remaining breeding sites in China. Six breast muscle tissues and 16 blood samples from 22 gulls and eight eggshell membrane tissues were collected for this analysis. The number of alleles per locus ranged from 4 to 15, with a mean of 8.9. The observed and expected heterozygosities ranged from 0.58 to 0.89 and 0.58 to 0.9, with means of 0.77 and 0.81, respectively. No significant linkage disequilibrium and no divergence from Hardy-Weinberg equilibrium were detected among these loci. Based on Micro-Checker tests, no null alleles are present at any of the loci. The microsatellite loci described here will be valuable for exploring population genetic structure and for other relevant genetic studies of Saunders's gull.