Patent ID: 8158355

Claim:
A method of obtaining a nucleotide sequence tag from a terminus of a nucleic acid, the method comprising the steps of: (a) providing a first nucleic acid sequence comprising a full-length first strand cDNA comprising a 5′ untranslated region, a coding sequence, a 3′ untranslated region and a poly A tail; (b) without prior cleavage of said first nucleic acid sequence, linking the 5′ end of said full length first strand cDNA to a linker sequence to form a linked nucleic acid, in which the linker sequence comprises: (i) a first recognition site for a first nucleic acid cleavage enzyme that allows cleavage of the first nucleic acid sequence at a site distant from the first recognition site, and (ii) a second recognition site for a second nucleic acid cleavage enzyme that allows nucleic acid cleavage at a site distant from the second recognition site, said cleavage site located at a position within the first recognition site; in which the linked nucleic acid has the structure: 5′-second recognition site-first recognition site-first nucleic acid-3′ (c) cleaving the linked nucleic acid with the first nucleic acid cleavage enzyme to provide: (i) a linked tag comprising the linker sequence linked to a nucleotide sequence tag representative of the first nucleic acid sequence, the nucleotide sequence tag comprising the 5′ terminus of the full length first strand cDNA; and (ii) a second nucleic acid sequence comprising a remainder portion of the first nucleic acid.