Genetic diversity analysis of Epinephelus fuscoguttatus (♀) and E. tukula (♂) hybrids

Abstract:

The genetic diversity of Jinhu grouper hybrids (Epinephelus fuscoguttatus ♀ ×E. tukula ♂) and their parents were analyzed via microsatellites. The results detected 215 alleles at 20 microsatellite loci, with an average polymorphic information content (PIC) of 0.638 6. The highest average effective allele number (Ne) was measured in E. fuscoguttatus (4.367 9), followed by the hybrids (3.370 6) and E. tukula (2.412 8). The average observed heterozygosity values (Ho) were 0.385 5 (E. tukula), 0.474 9 (E. fuscoguttatus), and 0.473 6 (hybrids), and the average PIC values were 0.491 9, 0.645 3, and 0.555 1, respectively. The three grouper populations were averaged to calculate the inbreeding coefficient (Fis; 0.228 0), total population inbreeding coefficient (Fit; 0.344 1), genetic differentiation coefficient (Fst; 0.150 4), and gene flow (Nm; 1.411 9), but differentiation among the populations was also observed. Cluster analysis, performed by the unweighted pair group method with arithmetic mean, placed the hybrids and E. fuscoguttatus into one group, indicating a close relationship. Prior studies showed that the Jinhu grouper is genetically diverse, which allowed for selective breeding, hybrid generation, and exploration of the genetic basis of heterosis.