Beyond MHC: signals of elevated selection pressure on Atlantic salmon (Salmo salar) immune-relevant loci.
Using Atlantic salmon (Salmo salar) as a model system, we investigated whether 18 microsatellites tightly linked to immune-relevant genes have experienced different selection pressures than 76 loci with no obvious association with immune function. Immune-relevant loci were identified as outliers by two outlier tests significantly more often than nonimmune linked loci (22% vs. 1.6%). In addition, the allele frequencies of immune relevant markers were more often correlated with latitude and temperature. Combined, these results support the hypothesis that immune-relevant loci more frequently exhibit footprints of selection than other loci. They also indicate that the correlation between immune-relevant loci and latitude may be due to temperature-induced differences in pathogen-driven selection or some other environmental factor correlated with latitude.
Tonteri
A
A
Division of Genetics and Physiology, Department of Biology, University of Turku, FIN-20014 Turku, Finland.
Vasemägi
A
A
Lumme
J
J
Primmer
C R
CR
D000818:Animals; D004777:Environment; D019143:Evolution, Molecular; D020224:Expressed Sequence Tags; D005787:Gene Frequency; D005828:Genetics, Population; D023281:Genomics; D005838:Genotype; D008285:Major Histocompatibility Complex; D018895:Microsatellite Repeats; D008957:Models, Genetic; D020317:Salmo salar / Q000235:genetics* / Q000276:immunology*; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA