Patent ID: 6203977
Filing Date: 2001-03-20
Classification: C12Q

Abstract:
A method of in situ hybridization to simultaneously detect multiple target sequences of interest in chromosomal DNA of interphase cells of nuclei thereof, the method comprising:(a) treating a sample of interphase cells or nuclei thereof to render chromosomal DNA present therein available for hybridization to sequences complementary thereto,(b) contacting said sample with a pool of DNA, wherein said pool comprises:i) different labeled DNA probes, each DNA probe comprising either DNA fragments labeled with a single fluorophores or a mixture of DNA fragments separately labeled with different fluorophores, such that each DNA probe generates an optically distinguishable signal, and each probe being specific for one human chromosome, of region thereof, suspected to be present in said sample; andii) competitor DNA fragment, wherein said fragments comprise repetitive sequeneces complementary to sequeneces present in said sample and to sequeneces present in said probes;under conditions that allow hybridization of said competitor DNA fragments to said complementary repetitive sequeneces present in said sample and present in said probes sufficient to suppress cross-hybridization between said repetitive sequeneces in said probes amd in said sample and allow hybridization of said probes to specific target chromosomal sequeneces present in said sample, andc) detecting multiple hybridization signals simultaneously, wherein each detected signals is distinguishable and identifies a specific target chromosomal sequenece present in said sample.