Nucleotide polymorphism and natural selection at the pantophysin (Pan I) locus in the Atlantic cod, Gadus morhua (L.).

摘要: Molecular studies of nucleotide sequence variation have rarely attempted to test hypotheses related geographically varying patterns natural selection. The present study tested the role spatially selection in producing significant linkage disequilibrium and large differences frequencies two common alleles at pantophysin (Pan I) locus among five populations Atlantic cod, Gadus morhua. Nucleotide sequences 124 Pan I showed strong evidence for an unusual mix balancing directional but no stable were highly divergent both level (differing on average by 19 mutations) amino acid (each having experienced three substitutions since diverging from a ancestral allele). All six occurred 56-residue intravesicular loop (IV1 domain) vesicle protein each involved radical change. An analysis molecular revealed heterogeneity recently derived mutations segregating within allelic classes, suggesting that selective sweeps may be presently occurring populations. dynamic nature polymorphism G. morhua clear departure equilibrium conditions invalidate simple model