Patent ID: 8574832

Claim:
A method comprising: a) providing; i) a biological sample comprising less than 50,000 cells, wherein said biological sample comprises genomic DNA; ii) a hairpin primer comprising at least one restriction enzyme binding site, at least one universal primer sequence ranging between four and thirteen nucleotides in length, and at least one random nucleotide sequence of at least eight nucleotides in length; iii) a second primer comprising said at least one restriction enzyme binding site sequence; iv) a restriction enzyme capable of creating a single nucleotide overhang at said restriction enzyme binding site sequences; and v) a polymerase; b) fragmenting said genomic DNA wherein a plurality of DNA fragments are created; c) extending said plurality of DNA fragments with said hairpin primer and said polymerase so as to create a first extension product; d) amplifying said first extension product with said second primer and said polymerase so as to create a second extension product, wherein the 3′ and 5′ ends of said second extension product each contain said restriction enzyme site sequence; e) cleaving the 3′ and 5′ ends of said second extension product at said restriction enzyme sites with said restriction enzyme, thereby creating a 3′ cleavage product and a 5′ cleavage product wherein each of said cleavage products are identical and comprise said single nucleotide overhang.