METHODS FOR NUCLEIC ACID MAPPING AND IDENTIFICATION OF FINE-STRUCTURAL-VARIATIONS IN NUCLEIC ACIDS

A method of juxtaposing sequence tags (GVTs) that are unique positional markers along the length of a population of target nucleic acid molecules is provided, the method comprising: fragmenting the target nucleic acid molecule to form target DNA insert; ligating the target DNA insert to a DNA vector or backbone to create a circular molecule; digesting the target DNA insert endonuclease to cleave the target DNA insert at a distance from each end of the target DNA insert yielding two GVTs comprising terminal sequences of the target DNA insert attached to an undigested linear backbone; recircularizing the linear backbone with the attached GVTs to obtain a circular DNA containing a GVT-pair having two juxtaposed GVTs; and recovering the GVT-pair DNA by nucleic acid amplification or digestion with endonuclease having sites flanking the GVT-pair. Cosmid vectors are provided for creating GVT-pairs of -45- to 50-kb separation sequencable by next-generation DNA sequencers.published_or_final_versio