Microarray

 A microarray is a two-dimensional array on a solid substrate, usually a glass slide or silicon thin-film cell that assays large amounts of biological material using high-throughput screening miniaturized, multiplexed and multiprocessing and detection methods. DNA microarrays are microscope slides that are printed with thousands of small spots in defined positions, with each spot containing a DNA sequence or gene which is known. Often, these slides are mentioned as gene chips or DNA chips. The DNA molecules that are attached to every slide act as probes to detect gene expression, which is additionally referred to as the transcriptome or the set of messenger RNA (mRNA) transcripts expressed by a gaggle of genes. Microarray analysis are often divided into two main steps: probe production and target (cDNA) production. Specific sequences are immobilized to a surface and reacted with labeled cDNA targets. a sign resulting from hybridization of the labeled target with the precise immobilized probe identifies which RNAs are present within the unknown target sample. To perform a microarray analysis, mRNA molecules are typically collected from both an experimental sample and a reference sample. Microarray provides a basis to genotype thousands of various loci at a time, which is beneficial for association and linkage studies to isolate chromosomal regions associated with a specific disease. This array can also be used to locate chromosomal aberrations associated with cancer, like segments of allelic imbalance, which may be identified by loss of heterozygosity.