Patent ID: 6475738
Filing Date: 2002-11-05
Classification: C12Q,Y02A

Abstract:
A method for detecting a nucleic acid insertion or deletion, the method comprising the steps of:(a) selecting a nucleic acid having a known wild-type sequence and having a target region comprising a polynucleotide repeat sequence having at most three different types of nucleotide bases selected from the group consisting of dGTP, dATP, dTTP, and dCTP; (b) contacting a sample with an oligonucleotide primer that is complementary to a portion of said nucleic acid immediately upstream of said target region; (c) extending said primer in the presence of nucleotide bases that are complementary to the nucleotide bases of the target region, thereby to form a primer extension product; (d) extending the primer extension product in the presence of a labeled nucleotide complementary to a nucleotide base downstream from the target region in said nucleic acid, wherein said labeled nucleotide is not complementary to any of the nucleotide bases of the target region selected in step (a), thereby to produce a labeled extension product comprising a sequence that is complementary to the entire target region; (e) detecting the labeled extension product; and (f) comparing the size of the labeled extension product detected in step e) to a standard, wherein a labeled extension product smaller than the standard is indicative of the presence of a deletion in the target region and a labeled extension product larger than the standard is indicative of the presence of an insertion in the target region.