Understanding the structure of the human genome has allowed scientists to study the actual function of specific genes, which is very important for understanding health and disease. DNA microarray is a technique that improves understanding of the genome from structure to function. A microarray is a laboratory technique used to detect the expression of thousands of genes at once. DNA microarrays are microscope slides printed with thousands of tiny dots in distinct locations, each containing a known DNA sequence or gene. These slides are called gene chips or DNA chips. Say no to plagiarism. Get a tailor-made essay on "Why Violent Video Games Shouldn't Be Banned"? Get an Original EssayThe DNA molecules attached to each slide act as probes to detect gene expression, also known as the transcriptome, or the set of messenger RNA (mRNA) transcripts expressed from a group of genes. This is a high-throughput, highly parallel RNA expression analysis technique that allows quantitative analysis of RNAs transcribed from both known and unknown genes. One of the most important aspects of this technique is that it provides diagnostic signs by comparing gene expression patterns in normal and pathological cells, since it can simultaneously monitor the expression levels of many genes, it also provides a source of operational context for predicting cellular control complex systems. To perform a microarray analysis, mRNA molecules are typically collected from both a test sample and a control or reference sample. For example, the reference sample could be from a healthy individual or one in whom a gene is expressed, and the sample to be tested could be collected from an individual with a disease such as cancer or a certain gene knockout. The two mRNA samples are then converted into complementary DNA (cDNA) and each sample is labeled with a different colored fluorescent probe. For example, the test cDNA sample can be labeled with a red or pink fluorescent dye, while the control cDNA can be labeled with a blue fluorescent dye. The two samples are then mixed together and allowed to bind to the microarray slide. The process in which cDNA molecules bind to DNA probes on the slide is called hybridization. After hybridization, the microarray is scanned to measure the expression of each gene printed on the slide. If the expression of a particular gene is higher in the test sample than in the control sample, the corresponding spot on the microarray appears pink/reddish. Conversely, if the expression in the test sample is lower than that in the control sample, the stain appears blue. Please note: this is just an example. Get a custom paper from our expert writers now. Get a Custom Essay Finally, if there is an equal expression in the two swatches, then the spot appears a mix of both colors, which could lead to considering the above-mentioned colors in a magenta color. This data collected via microarrays can be used to create gene expression profiles, which highlight the importance of microarrays in showing instantaneous changes in the expression of many genes in response to a particular condition or treatment.