Features:
- Build the alignment by series of pairwise alignments following the
branching order in a phylogenetic tree (see
Distance based methods)
- Build an initial alignment starting with the most related sequences
- Gradually add in the most distant sequences
- Alignments sequence-sequence, sequence-alignment, alignment-alignment
Drawbacks:
- Greedy algorithm: Local minimum problem. Dependence on the initial
pairwise alignment. Solution: Stochastic or iterative methods.
- The choice of alignment parameters: when adding more distantly related
sequences to the msa, we are dealing with different evolutionary distances so that
the substitution matrix and the gap penalties must be different on every
stage.
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