Multiple Alignment Pairwise alignment Example-4 sequences SI S2 S3 S4 6 pairwise comparisons then cluster analysis Multiple alignment following the tree from A Gaps to optimize alignment New gap to optimize alignment of(S,S4) with(S,S3) align alignments-preserve gapsPairwise Alignment Steps in Multiple Alignment Multiple alignment following the tree from A S1 S1 S1 6 pairwise comparisons then cluster analysis similarity align most similar pair Gaps to optimize alignment New gap to optimize alignment of (S2S4) with (S1S3) align next most similar pair align alignments-preserve gaps Example - 4 sequences S1 S2 S3 S4 S2 S2 S2 S3 S3 S3 S4 S4 S4 S1 S2 S3 S4