What does SDM mean in UNCLASSIFIED

Definition

Site directed mutagenesis (SDM) is a laboratory technique used by biologists to introduce changes into specific bases at targeted sites within a nucleic acid sequence, such as double-stranded DNA or RNA strings. By targeting a specific location on the DNA strand, researchers can induce mutations that alter gene expression and protein structure; thereby allowing them to investigate the effects of various changes on biological pathways and processes.

Process

Site-directed mutagenesis typically begins with designing oligonucleotide primers that will carry out the desired sequence changes when applied during PCR amplification. The primer must be designed so that it complements the template sequence at all locations except for the mutation site(s). To create a double-stranded DNA construct with mutated sequences, two primers are synthesized—one carrying the wild type (normal) sequence, while the other carries the desired mutant sequence. When both primers are applied together in a PCR reaction, amplification of only those strands possessing mutations in their respective templates occurs.

Applications

SDM technology is widely used across several fields today, from pharmaceuticals and biotechnology to forensic science and plant biology. This method has proven particularly useful for introducing changes into genes linked to disease states or identifying genetic differences between individuals or species. Further applications include the creation of libraries of small proteins for structure-function analysis, production of antibodies against mutated antigens for targeted therapy development, mapping functional sites on enzyme proteins, developing novel reagents for diagnostics assays, generating chimeric organisms for pathogen studies among many others uses.