Developmentof 84 single nucleotide polymorphism (SNP) markers for the three-spot swimming crab (Portunus sanguinolentus) by using RAD appoach Guidong Miao1,2,3 Feng Wang1,2,3 Jihua Guo1,2,3, Pei Zhang1,2,3 Hongyu Ma4

Abstract The three-spot swimming crab (Portunus sanguinolentus) is one of most important large size economic crab in China. In this study, we first isolated and characterized a set of 84 SNP loci in P. sanguinolentus. 10 pairs of primers PCR products were sequenced and a total of 3181bp high-quality DNA sequences were obtained from which 84 polymorphic SNP loci were identifed and 84 SNP loci were identified and accurated genotyped. The average frequency of SNP loci was one locus every 38 base pairs in P. sanguinolentus genome. Of these 84 SNP loci, each had bi-alleles with the minor allele frequency ranging from 0.0167 to 0.5000. The observed heterozygosity varied from 0.0333 to 0.7143, while the expected heterozygosity ranged from 0.0333 to 0.5085 per locus. 51 loci showed low variation (HO ≤ 0.3) and fourteen SNP loci showed high variation (HO ≥ 0.5). Among 84 SNP loci, 11 loci showed significant deviation from Hardy–Weinberg Equilibrium. The SNP markers developed herein will provide valuable information for elucidating population genetic diversity, population dynamics, and conservation genetics of this germplasm resource and other related crab species.