Microarray+Analysis

Microarray analyses are used in genetics to determine whether or not particular genes are expressed in an individual. This process involves lysing a cell in order to isolate mRNA, which is then made into cDNA, and is then spotted with multiple identical strands of DNA on a microarray plate, each spot representing one gene. This allows scientists to experiment with thousands of copies of DNA, and therefore yields a significant amount of genetic data used to describe which genes are turned on or off (The University of Utah, 2013). Figure 1 below describes how the technique is used to compare DNA between individuals: Figure 1. Depiction of microarray techniques in comparing DNA from 2 individuals (Source: []).

By using microarray analyses, researchers can learn more about different genetic disorders, a main focus in recent years being on cancer. Classifying cancer types based on pattern of gene activity in tumor cells can lead to the most efficient treatments, and microarray analyses are simple and cost-efficient experiments that allow for such data to be collected (National Human Genome Research Institute, 2011). Key individuals involved in the discovery and use of the technique includes Patrick O. Brown, Joseph DeRisi, and David Botstein (Hoopes, 2008). These researchers are responsible for the development microarray analyses in the mid-1990’s, and the technique has since become a major method used in the scientific community. In an article to be published in 2014 in China, researchers described an experimental method in which cDNA microarray analyses used to describe expressed novel genes involved in plant responses to drought (Fan et. al., 2014). Their results show a table in which expressed genes for drought stress are described, as well as how long each gene is and their values of expression. Another article published in 2013 shows how gene expression profiles can be used to better understand pathophysiology of a disorder known as Preeclampsia (Song et. al., 2013). Their analysis using microarray techniques aided in the identification of three differentially expressed genes that are involved in the disorder, and accompanied by a Connectivity Map database they were able to provide potential therapeutic agents. A third study provided details into new technology regarding microarray analyses. A study done in Italy for 2014 publication used high-sensitivity microarray technology to achieve fluorescence enhancement as well as using a new substrate composed of a thin aluminum mirror and a quarter wave silicon oxide (Cretich et. al., 2014).

References:

Cretich, M., Galati, C., Renna, L., Condorelli, G. G., Gagni, P., Chiari, M. (March 2014). Characterization of a new fluorescence-enhancing substrate for microarrays with femtomolar sensitivity. Sensors and Actuators B: Chemical. (192) 15-22.

Fan, Q., Yan, F., Qiao, G., Zhang, B., Wen, X. (January 2014). Identification of differentially-expressed genes potentially implicated in drought response in pitaya (//Hylocereus undatus)// by suppression subtractive hybridization and cDNA microarray analysis. Gene. (533:1) 322-331.

Hoopes, Laura. (2008). Genetic Diagnosis: DNA Microarrays and Cancer. Nature Education. (1:1) 3.

National Human Genome Research Institute. (November 2011). DNA Microarray Technology. National Institutes of Health. Online. [|http://www.genome.gov/10000533#top]

Song, Y., Liu, J., Huang, S., Zhang, L. (December 2013). Analysis of differentially expressed genes in placental tissues of preeclampsia patients using microarray combined with the Connectivity Map database. Placenta. (34:12) 1190-1195.

The University of Utah. (December 2013). Profiling Technique: Microarray Analysis. Learn. Genetics. Online. []