Gene-associated microsatellite markers confi rm panmixia and indicate a diff erent pattern of spatially varying selection in the endangered Japanese eel Anguilla japonica

摘要

The Japanese eel(Anguilla japonica)is a commercially important fi sh species in East Asia and its recruitment has been rapidly declining since 1990s.Clarifying the genetic population structure of A.japonica is the basis of multinational cooperation on its management and protection,due to its large distribution range.Gene-associated markers have been proved powerful in delineating fi ne-scale population genetic structure and spatially varying selection.In the present study,we developed 24 polymorphic gene-associated microsatellite markers including 18 loci associated with the genes under selection in the two North Atlantic eel species(Anguilla anguilla and Anguilla rostrata)and 6 loci based on transcript sequences.A total of 13 geographic populations were sampled across its distribution range,including 11 samples from China(9 from China’s mainland and 2 from Taiwan region),and 2 samples from Japan.A total of 416 individuals(mostly glass eels)were collected and genotyped at the 24 microsatellites.All measures of diff erentiation were accordant with a panmictic scenario(F ST=-0.001)in A.japonica.No footprints of spatially varying selection were found,indicating that the selection pattern in A.japonica might be diff erent from that in the two North Atlantic eel species.We suggest that A.japonica should be managed as a single unit and management and conservation eff orts must be coordinated at the international level,as overexploitation in any region will decrease its recruitment across the whole distributional range.