Microarrays

Abstract

DNA microarrays are one of the key new technologies in biology. A microarray is a solid surface, typically a microscope slide or silicon chip, to which short DNA molecules (probes) are bonded in a regular array of thousands of tiny spots. Each spot, or feature, has a specific DNA sequence and is located at a known place in the array. The probes are designed to bond by Watson-Crick hybridization to the DNA molecules in a target sample which typically consists of either cDNA reverse transcribed from mRNA, or genomic DNA. Hybridization of the target to the probes is usually detected and quantified by fluorescence from the fluorescently labeled target molecules. The result is a quantitative measure of the relative abundance of DNA sequences in the target. This information can be used in a variety of ways, including