Abstract.
We sequenced exon 2 of the MHC class II B gene in Atlantic salmon from the Baltic Sea and identified 17 different exon 2 alleles among 22 different restriction fragment length polymorphism haplotypes. The sequences differed at between 1 and 34 bases. Two different tests were used to estimate the importance of recombination in the generation of new alleles. Recombination events appear to have occurred between three and nine times. Only two pairs of sequences differed by less than five nucleotides, minimizing the importance of point mutations for generating new alleles. Phylogenetic analysis showed that sequences did not cluster according to populations, and genetic distances between populations were small compared to those obtained by allele frequency data. These results, together with the similarity found between exon 2 sequences from Baltic salmon and Norwegian salmon, indicate that all of the identified alleles were present in the ancient salmon population colonizing the Baltic rivers after the last glaciation.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Electronic Publication
Rights and permissions
About this article
Cite this article
Langefors, Å., Lohm, J. & von Schantz, T. Allelic polymorphism in MHC class II B in four populations of Atlantic salmon (Salmo salar). Immunogenetics 53, 329–336 (2001). https://doi.org/10.1007/s002510100329
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/s002510100329