DNA Microarray and Bioinformatics Technologies: A mini-review

Abstract

This bibliographic review gives a concise overview of how DNA microarrays became one of the most important recent technologies. In brief, DNA sequences acting as probes are fixed on tiny slides in arrays to identify the presence of tagged fluorescently nucleic acids from a certain sample. The nucleic acids having complementary sequences with probes will hybridize on the array slides and because they are labeled, they are detected easily using specialized scanner and software. According to the way DNA microarrays are manufactured, there are three main types including spotted arrays, in situ synthesized arrays, and self-assembled arrays. Bioinformatics, which is the use of mathematical and computational methods, plays a crucial role in this technology as it is used for designing specific primers and probes suitable for each sample that is investigated. Moreover, although DNA microarrays are widely used to determine gene expression levels, they are also used in single nucleotide polymorphism (SNP) genotyping. For this application itself, more than one approach can be used including allele discrimination using hybridization, array primer extension assay (APEX), and Illumina infinium assay. The APEX approach was discussed in more detail as it was found that to be useful in screening for inherited genetic diseases such as Stargardt disease. Finally, this review was ended with short discussion of some DNA microarray limitations arising hybridization kinetics as well as difficulties in designing arrays for highly variable genomes.