Pulsed Field Gel Electrophoresis (commonly abbreviated as PFGE) is a method for separating large DNA molecules, which may be used for genotypingGenotyping refers to the process of determining the genotype of an individual with a biological assay. Current methods of doing this include PCR, DNA sequencing, and hybridization to DNA microarrays or beads. The technology is intrinsic for test on father-/motherhood and in clinical research for the investigation of disease-associated genes. Due to current technological limitations, almost all genotyping is partial. That is, only a ...genotyping or genetic fingerprintingGenetic fingerprinting, DNA testing, DNA typing, and DNA profiling are techniques used to distinguish between individuals of the same species using only samples of their DNA. Its invention by Sir Alec Jeffreys at the University of Leicester was announced in 1985. Two humans will have the vast majority of their DNA sequence in common. Genetic fingerprinting exploits highly stable repeating sequences called minisatellites. Two unrelated humans will be unlikely to have the same numbers of minisatellites at ...genetic fingerprinting.
It is labor intensive and differs from normal agarose gel electrophoresisAgarose gel electrophoresis is a method used in biochemistry and molecular biology to separate DNA, RNA, or protein molecules by size. This is achieved by moving negatively charged nucleic acid molecules through an agarose matrix with an electric field (electrophoresis). Shorter molecules move faster and migrate further than longer ones.Sambrook J, Russel DW (2001). Molecular Cloning: A Laboratory Manual 3rd Ed. Cold Spring Harbor Laboratory Press. Cold ...agarose gel electrophoresis by the use of an alternating electrical field (hence the name). Under normal electrophoresis, large nucleic acid particles (above 30-50 kb) migrate at similar rates, regardless of size. By changing the direction of the electric field frequently, much greater size resolution can be obtained. The true theoretical basis of this effect is not clearly understood (numerous models have been put forward), but generally speaking, the smaller nucleic acid pieces are able to re-orient to the new field more quickly than are larger ones. This delay in re-orientation means larger pieces end up migrating down the gel slower than smaller, more nimble ones. Frequent changing of the migration direction means that over the entire run, the movement sums to one direction.
It is commonly considered a gold standardIn medicine, a gold standard test is a diagnostic test or benchmark that is regarded as definitive. This can refer to diagnosing a disease process, or the criteria by which scientific evidence is evaluated. For example, in resuscitation research, the gold standard test of a medication or procedure is whether or not it leads to an increase in the number ...gold standard in epidemiologicalEpidemiology is the study of factors affecting the health and illness of populations, and serves as the foundation and logic of interventions made in the interest of public health and preventive medicine. It is considered a cornerstone methodology of public health research, and is highly regarded in evidence-based medicine for identifying risk factors for disease and determining optimal treatment approaches to clinical practice. The work of communicable and non-communicable ...epidemiological studies of pathogenicA pathogen or infectious agent is a biological agent that causes disease or illness to its host.http://www.medterms.com/script /main/art.asp?articlekey=6383 Definition of pathogen The term is most often used for agents that disrupt the normal physiology of a multicellular animal or plant. However, pathogens ...pathogenic organismsIn biology and ecology, an organism (in Greek organon = instrument) is a living complex adaptive system of organs that influence each other in such a way that they function in some way as a stable whole. The origin of life on Earth and the relationships between its major lineages are controversial. Two main grades may be distinguished, the prokaryotes and eukaryotes. The ...organisms. Subtyping has made it easier to discriminate among strains of Listeria monocytgenes and thus to link environmental or food isolates with clinical infections.
