DNA chips: analysing sequence by hybridization to oligonucleotides on a large scale

Complete sequences of genomes and comprehensive sets of cDNA sequences open the way to a huge range of biological problems. There is a need for analytical methods that can deal with the large number of sequences in the data banks and, ideally, we would like to analyse all sequences together. Gel-based sequencing is a serial process that analyses one sequence at a time. Oligonucleotide arrays, or ‘DNA chips’, are miniature, parallel analytical devices, which could bring to sequence analysis and molecular genetics many of the advantages that semiconductor devices brought to computing.