Figure 1
From: Databases of homologous gene families for comparative genomics
Removal of incompatible HSPs. For each couple of homologous sequences found by BLASTP, HSPs that are incompatible with a global alignment are removed. In this example, segments S1 and S2 are compatible, but segments S3 and S4 are not. They are therefore ignored by further computations on similarity measures which allow one to classify (or not) these two sequences in the same family.