Patent ID: 8021842

Claim:
A method of screening for the presence or absence of a nucleotide allele of a polymorphism in multiple DNA samples, the method comprising the steps of: combining the following under hybridization conditions: (i) a mixture comprising single stranded DNA fragments derived from multiple DNA samples, wherein the single stranded DNA fragments comprise: (a) a unique tag corresponding to the DNA sample from which it is derived; and (b) a sequence of interest having a polymorphic site, the polymorphic site having a wild type nucleotide allele and a second nucleotide allele; and (ii) RNA probes comprising a sequence complementary to the sequence of interest having the wild type nucleotide allele at the polymorphic site; thereby forming RNA/DNA heteroduplexes; removing any mismatched nucleotide at the polymorphic site from the RNA probes in the heteroduplexes; contacting the heteroduplexes with a nucleotide triphosphate complementary to the second nucleotide allele under nucleic acid polymerization conditions; isolating heteroduplexes that have incorporated the nucleotide triphosphate complementary to the second nucleotide allele; and determining the unique tags of the single stranded DNA fragments of the isolated heteroduplexes to identify genomic DNA samples having the second nucleotide allele at the polymorphic site in the sequence of interest, thereby screening the multiple DNA samples for the presence or absence of the second nucleotide allele.