Isocaudomers are pairs of restriction enzymes that have slightly different recognition sequences, but upon cleavage of DNA, generate identical overhanging termini sequences.
For example the enzymes Mbo I and BamH I are isocaudomers: N represents any of the four nucleotides.
Independently of which nucleotide is present when cleaving with MboI, after cleavage with either enzyme, all termini have the central tetranucleotide - GATC.
This can be used for elimination of restriction sites from the resulting DNA fragment.
However, resulting DNA sequence will be: where the nucleotides shown in italic originate from NotI-cut site, and those in bold from Bsp120I-cut one.