Identification and analysis of mutations is an important technique in the molecular biologist’s toolbox. Mostly mutation analysis and screening techniques can be used for mutation detection as either our primary source, or as a confirmation of next generation sequencing and microarray results. Over the past double of decades, many mutation analysis and detection techniques have helped the researchers with their identification.
Techniques for Mutation Detection
· Denaturing gradient gel electrophoresis (DGGE)
· Constant denaturing gel electrophoresis (CDGE)
· Temporal temperature gradient gel electrophoresis (TTGE)
· Single-strand conformation polymorphism (SSCP)
· High resolution melt (HRM) analysis
All of these recently used techniques need DNA amplification via PCR before the technique can be used. Typically, site-directed mutagenesis is used to create mutant control samples by introducing mutations into some DNA fragments. DNA sequencing can be used to verify the mutation after any of these techniques.
With the arrival of new technologies for more accurate understanding of the genome and potential gene therapies, the detection of mutations has an increasingly central role in many areas of genetic diagnosis including pre-usage of genetic diagnosis (PGD), prenatal diagnosis (PND), pre-symptomatic testing, conformational diagnosis and forensic/identity testing. Two groups of tests, molecular and cytogenetic, are used in genetic syndromes. In general, single base pair mutations are identified by direct sequencing, DNA hybridization and/or restriction enzyme digestion methods.
However, there are two main approaches for genetic diagnosis;
· The indirect approach depends on the results from a genetic linkage analysis using DNA markers such as STR(short tandem repeat) or VNTR (variable number tandem repeat) markers flanking or within the gene.
· The direct approach for diagnosis essentially depends on the detection of the genetic variations responsible for the disease.
GENEWIZ’s Mutation Analysis service assists scientists and researchers ramp up mutation detection in coding exons, enabling scientists to quickly analyze and identify mutations that may affect the function of their gene of interest. No matter the application, use GENEWIZ’s expertise in targeting genomic regions of DNA with specific, robust assays.
The groundwork for the mutational analysis of biochemical, cellular, and developmental pathways are the basis for mutation analysis and their understanding.
The common situation is that the researcher is interested in some particular biological process and wishes to use the genetic approach to dissect this process. The goal and the challenge are to identify all of the genes that take part in the process and then to understand the nature of the gene products (usually proteins) and how they contribute and interact in this process or pathway. Genes are usually identified through their mutant alleles; therefore the genetic approach begins with mutants.
Normally, the following steps are followed to genetically cut up a process:
· Design an effective mutation-detection system.
· Use a mutagen to induce a large collection of mutants that show variations in the wild-type process.
· Group the mutations into the grouped genes by utilizing the complementation tests.
· Map the genes to their chromosomal loci.
· Isolate the genes by using DNA technology.
· Characterize the structure and function of the genes.
There is a large gap between the expectation of the different kinds of mutations that could occur in a gene and the actual recovery of mutations after mutagenesis. Certain factors are necessary in the practical recovery of mutants. The choice of mutagen is important, because different mutagens will generate a different mutational array. The phenotypes that are used to identify mutant-bearing individuals also are important, because only a subset of the huge array of mutations that can arise in a given gene might lead to the production of the relevant mutant phenotype.