Distribution of genetic variation in the growth hormone 1 gene in Atlantic salmon (Salmo salar) populations from Europe and North America

摘要: The level and hierarchical distribution of genetic variation in complete sequences the Atlantic salmon (Salmo salar) growth hormone (GH1) gene were investigated populations from Europe North America with a view to inferring major evolutionary forces affecting at this locus. Seventeen polymorphic sites identified nine populations, levels noncoding (intron untranslated region sequences) nucleotide diversity being similar those observed other species. No variation, however, was exonic sequences, indicating that GH1 is three 25 times less than estimated for human Drosophila coding respectively. This suggests purifying selection predominant contemporary force controlling molecular evolution sequences. Comparison haplotype relationships within between indicated differentiation greater within-continent comparisons. However, several haplotypes northernmost European more American any Europe. most likely be result historical, rather contemporary, flow. Neutrality test statistics, such as Tajima's D, significantly positive which American-like observed. Although D commonly interpreted signal balancing selection, explanation case either historical migration or ascertainment bias, population local adaptation, has given rise an excess intermediate frequency alleles.