DNA hybridization exploits complementary base pairing between a known immobilized probe sequence and labeled nucleic acid from a sample so that the amount bound reports the abundance of the corresponding transcript. A microarray applies this principle in parallel: a chip bearing thousands of spatially indexed wells, each holding probes complementary to one gene, is exposed to differentially fluorescently labeled nucleic acid from two cell populations, and the ratio of the two label intensities at each position classifies that gene as upregulated, downregulated, or unchanged between conditions. The technique belongs to molecular biology and functional genomics, providing a genome-scale assay of transcriptional profiles whose comparative readout underlies expression-based disease characterization and targeted therapeutic selection.
DNA hybridization exploits complementary base pairing between a known immobilized probe sequence and labeled nucleic acid from a sample so that the amount bound reports the abundance of the correspon…