Global and local alignment

There are two different approaches to aligning two sequences. A global alignment is an alignment of the entire length of both sequences, while a local alignment only aligns the regions of the sequences that are similar. Global alignment is useful for comparing two sequences that are expected to be similar overall, but may have some differences. While local alignment is useful for finding similar regions within two longer sequences that may have many differences overall. Local alignments are often used to identify functional or structural motifs within a sequence.

Meet the family: global and local alignment

Practical: Implementing global alignment

Read alignment in the field

Problems to solve (advanced)

Try to solve these problems after completing this section.

1. Global Alignment with Scoring Matrix

2. Maximizing the Gap Symbols of an Optimal Alignment

3. Global Alignment with Constant Gap Penalty

4. Local Alignment with Scoring Matrix

Congratulations!

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