RAPD analysis of molecular genetic diversity and genetic relationship of four grouper species

The RAPD(randomly amplified polymorphic DNA) technology was applied to studying the genetic diversity and genetic relationship of four grouper species,including two raised population(Epinep helusmalabaricus from Hainan,China and E.coioides from Guangdong,China) and two wild populations(E.firio and E.merracaptured from the South China Sea.25 random primers were used to be analyzed,and the genetic relationship of these grouper species was analyzed by UPGMA.The results indicated that:first,the percentages of polymorphic loci of the wild populations of E.frio and E.merra were 58.07% and 55.65%,and the mean heterozyg ositys of the wild populations of E.frio and E.merra were 0.1793 and 0.1622,respectively,the level of genetic diversity of them was high and the genetic status was good.However,that of the raised populations of E.malabaricus and E.coioides was low.The percent ages of polymor phicloci were 49.70% and 40.38%,and the mean heterozygositys were 0.1349 and 0.1135 respectively,which indicated the level of genetic diversity of the raised grouper populations was declined,and it should be taken some remedial measures.Second,the interspecies genetic distance and clustering analysis showed that:among four grouper species,the genetic distance between E.malabaricus and E.coioides was minimum(0.2570),E.frio and E.merra took second palace(0.5146),E.coioides and E.firio was maximum(0.5810).Finally,among the fragments generated by 8 primers,some specific fragments which can be used to identify these groupers,were found.