Patent ID: 7601499

Claim:
A method for obtaining a DNA construct comprising two end regions of a target nucleic acid comprising the steps of: (a) fragmenting a large nucleic acid molecule to produce a target nucleic acid; (b) ligating a hairpin adaptor to each end of said target nucleic acids from step (a), digesting with exonuclease to remove nucleic acids with exposed 5′ or 3′ ends and cleaving said hairpin adaptors to create sticky ends for circularization; (c) ligating a signature tag to said sticky ends to form a circular nucleic acid molecule; (d) digesting said circular nucleic acid with a restriction endonucleases which cuts said target nucleic acid but which does not cut said hairpin adaptor or said signature tag to produce said DNA construct comprising two end regions of a target nucleic acid; (e) ligating a PCR primer to each end of said DNA construct; and (f) amplifying said DNA construct by PCR.