Identification of palearctic coregonid fish species using mtDNA and allozyme genetic markers

Two types of molecular genetic markers were used for genetic identification of species and local stocks of palearctic coregonids (Coregonidae, Salmoniformes, Teleostei). Seven nominate species of whitefishes and ciscoes Coregonus spp. of Eurasia Arctic Sea basin and inconnu Stenodus leucichthys nelma represented by specimens from North America were studied. Using restriction analysis of PCR-amplified products of the ND-1 gene of mitochondrial DNA (mtDNA) and allelic composition at several allozyme loci discrimination was successful between C. lavaretus pidschian Siberian whitefish, C. nasus broad whitefish, C. autumnalis Arctic cisco, C. migratorius Baikal omul, C peled peled, and C. sardinella least cisco. Muksun C. muksun was indistinguishable from Siberan whitefish. Creatine kinase (CK) isozyme patterns and Rsa I restriction patterns of ND-I were the most effective markers allowing discrimination among species. Intra-specific differentiation in mtDNA was found in all species but was much less pronounced than inter-species variation. In several specimens composite haplotypes typical of another species were found that reflect probable gene introgression by hybridization. A combination of mtDNA and nuclear genetic markers is suggested for reliable identification of both typical species representatives and hybrids. (C) 2000 The Fisheries Society of the British Isles.