Algorithms for high-density oligonucleotide array.

As a global gene expression-monitoring tool, high-density oligonucleotide arrays (HDAs), accelerate biological and drug discovery processes. Computational considerations affect several key issues, from array design and accurate gene expression level determination to various aspects of the biological analysis of cell functions and gene networks. This review highlights recent progress in ideas and algorithms that are specific to HDAs. Replacing a large number of specific 'mismatch' oligonucleotides by a small number of general noise control oligonucleotides and using dynamic probe-to-gene mapping were some of the ideas proposed. Several novel mismatch-free probe-to-gene condensation algorithms have demonstrated the ability to take advantage of such designs, and provide higher density and equivalent or better calculation accuracy than previous algorithms. Algorithms to be developed in the future should significantly increase both the quality and quantity of information revealed by a single array; therefore, a single array containing the whole mammalian genome or even multiple genomes could soon become a standard tool.