Multiple alignment of the amino acid sequences of NILT Ig domains from the Atlantic salmon. Characteristic residues are highlighted in black and gray. Dots (.) indicate identity to Ssa-NILT1 Ig1 and dashes (-) denote gaps introduced for optimal alignment. Below is a rooted phylogenetic tree showing the division into different groups of NILT Ig domains from the Atlantic salmon. The unrooted tree was built by the neighbour-joining method using Clustal W  and the MEGA 4  packages and bootstrapped 10,000 times.