ISOLATION AND CHARACTERIZATION OF MICROSATELLITE MARKERS FROM cDNA LIBRARY OF SOLEN GRANDIS

The distribution of 2—6bp simple sequence repeats(SSRs) were analyzed from cDNA Library(2038 ESTs) of Solen grandis using the software SSRIT.When the minimum repeats were assigned as 5,96 sequences were found to contain microsatellite sequences(taking 4.71%).Up to 103 microsatellite loci were obtained,among which the dinucleotide repeats motifs were the most abundant type(taking 74.76%),followed by trinucleotide and tetranucleotide repeats of 22.33%,2.91% respectively,and pentanucleotide and hexanucleotide repeats were not found.14 primer pairs were designed with Primer 3 software from EST sequences containing microsatellites,and 5 primers had polymorphic PCR products in Nantong wild population by PCR and polyacrylamide gel electrophoresis analysis.In these 5 microsatellite loci,the allele numbers,the observed heterozygosity and expected heterozygosity distributed from 2 to 7,0.067 to 1.000 and 0.066 to 0.775,respectively.Shannon's diversity index ranged from 0.146 to 1.545.The results showed that 5 microsatellite loci were suitable for genetic analysis.