One of the most exciting nucleic acid analysis techniques is microarrays or DNA chips. They provide a radically different approach to large-scale analysis and qualification of genes and gene expression patterns. A microarray consist of an ordered arrangement of hundreds or thousands of DNA sequences such as oligonucleotides or cDNAs deposited onto a solid surface approximately 1,2 x 1,2 cm. The microarray technique is based on hybridization of nucleic acids. Sequence complementarity provides the hybridization between two single-stranded nucleic acid molecules, one of which is immobilized on a matrix.
There are two variants of the chips; cDNA microarrays and oligonucleotides arrays. Both of them can be used to analyze gene expression patterns, however there are important differences between them. They differ in the size of the arrayed nucleic acids.
…