Analysis of genetic diversity of nine families of Pinctada fucata

We studied the genetic diversity of breeding family of Pinctada fucata. Six microsatellite markers were chosen for genetic analysis of 360 individuals of nine families. A total of 32 alleles were detected and the number of allele at each locus was 3~8. The effective allele was 1.758 7~3.586 5. The observed heterozygosity (H_o) was 0.144 4~0.488 9. The expected heterozygosity (H_e) was 0.432 0~0.722 2 and the Shannon index was 0.691 9~1.507 4. Monomorphism loci were found in each family. The average H_o (0.129 2~0.466 7), average H_e (0.155 0~0.439 6) and Shannon index (0.248 5~0.712 2) were detected in family population. Nineteen loci (35.19%) were deviated from Hardy-Weinberg equilibrium test significantly. The genetic distance was 0.109 0~1.137 2 and the genetic identify index was 0.320 7~0.896 8. L₄B₄6 was the furthest with L₄B₄8 and the nearest with D₃D₃13 in terms of genetic distance. Nei′s genetic distance was used to construct the dendrogram by using the unweighted pair group method with arithmetic (UPGMA). Nine families were divided into three clusters: family L₄B₄8 clustered alone and layed outside, while three families (B₄D₄26, B₄D₄27 and D₄B₄45) clustered together, and the other families clustered into one clade. The study provides references for construction of next generation of nuclear populations in P. fucata selective breeding.