Pyrophosphorolysis activated polymerization on one end 2

Method for removing one end nucleotide 2 'of an oligonucleotide comprising: incubating at least one target nucleic acid: pyrophosphate at least a first biocatalyst comprising an activity pyrophosphorolysis, and at least one oligonucleotide comprising one end nucleotide 2' , said oligonucleotide at least partially complementary to at least a first subsequence of the target nucleic acid under conditions in which the first biocatalyst removes at least the end nucleotide 2'oligonucleotide producing an end nucleotide 2'removed and an oligonucleotide shortened , thereby removing the nucleotide oligonucleotide