Genetic variation of Chinese and Japanese wild Pacific abalone(Haliotis discus hannai) measured by microsatellite DNA markers

Population differentiation and relationships among three wild populations of the Pacific abalone Haliotis discus hannai collected from coastal seas around China and Japan were estimated using microsatellite DNA analysis. The results obtained with six microsatellite loci showed a high genetic diversity for China and Japan populations. The mean number of alleles per locus ranged from 11.7 to 23.0, and the average of observed and expected heterozygosity ranged from 0.656 to 0.721, and from 0.721 to 0.793, respectively. The observed genotype frequencies at each locus were mostly in agreement with Hardy-Weinberg expectations with five exceptions. Significant differences were detected between Chinese and Japanese H. discus hannai populations[Weir and Cocker-ham's fixation index (F_st) range:0.020~0.023; Slatkin's fixation index (R_st) range:0.016~0.044], and no obvious difference was detected between the samples of Japanese H. discus hannai populations (F_st=0.002; R_st=0.007). The level of differentiation among populations is further evidenced by the nNeighbor-joining tree topology on which the Japanese samples were closely clustered, and the Chinese population formed a separate cluster. These results suggest that care should be taken in future management of different populations.