Abstract:Babylonia lutosa is a marine shellfish that has high economic values. In recent decades, the natural resource of B. lutosa has declined due to the environment destruction and overfishing. To further understand the level of genetic diversity and population genetic structure of B. lutosa, we have evaluated the information characteristics of B. lutosa’s microsatellites, after obtaining transcriptome sequences using MISA software. The results show that a total of 16342 microsatellites and 181 nucleotide repeat motifs were identified. Different types of repeat microsatellites had considerably different distribution characteristics. Mononucleotide and dinucleotide microsatellite repeating units were the most abundant in the B. lutosa transcriptome, in which 6 repeats of AC/GT (70.58%) were the dominant repeating dinucleotide units. The length of the dominant repeating units was 12~20 bp (63.95%) and 21~25 bp (9.14%), respectively, and the average length was 18.4 bp. Among the 50 designed primer pairs, 23 proved to be polymorphic microsatellite markers in the B. lutosa wild populations (WP). The results showed that the allele number of these microsatellites ranged from 2 to 7. The expected heterozygosity (He) and observed heterozygosity (Ho) ranged from 0.190 to 0.937, and 0.065 to 0.936, respectively. The polymorphism information content (PIC) ranged from 0.061 to 0.777. The He values of the WP and breeding population (BP) were 0.491 and 0.544, respectively. The Ho values of the WP and BP populations were 0.477 and 0.564, respectively. The PIC values for WP and BP were 0.541 and 0.407, respectively. There were 13 population loci that were heterozygote excesses in WP, and 13 population loci in BP. The genetic differentiation index (Fst) ranged from 0.001 to 0.655, with an average value of 0.053 (0.05
