GENETIC-DIVERGENCE AT THE NAD-DEPENDENT MALIC ENZYME LOCUS IN ATLANTIC SALMON FROM EUROPE AND NORTH-AMERICA()

The distribution of genetic variation for NAD+ malic enzyme (ME) poly morphism in the Atlantic salmon was assessed in both anadromous and re sident populations. The analysis revealed a major allelic divergence b etween North America and Europe. The 80 variant occurred in 39 of 40 North American samples, ranging in frequency from 0 to 0.515. In contr ast, it was detected in only three fish from two of the 35 European lo cations analysed. Eleven fish from two rivers in north-west France had the 110 variant. While heterogeneity among North American population s was significant, no regional differentiation was apparent and anadro mous and resident salmon were not found to differ. (C) 1997 The Fisher ies Society of the British Isles.