Alignment of salmonid MHC class II beta sequences. Sequence references are as follows: Sasa-DBB (630N19) [Genbank: DY726096], Sasa-DAB [Genbank: CAD27784], Onmy-DBB [Genbank: AAD53026], Onmy-DAB [Genbank: AAA79133]. Dots indicate identities, dashes indicate gaps or missing sequence information. Cysteine residues involved in putative Ig fold are bold and underlined, and the unique N-linked glycosylation sites found in salmonids are boxed. Individual domains and regions are defined based on mammalian class II sequences.