Stringency
Definition
The extent to which hybridisation conditions favour only perfectly complementary probe-target pairs over partially mismatched ones. High stringency (elevated temperature and/or low salt concentration) minimises non-specific hybridisation; low stringency allows detection of related but non-identical sequences.
- Governs
- Hybridisation specificity
- High stringency conditions
- Elevated temperature, low salt
- High stringency effect
- Minimises mismatched binding
- Used in
- Southern, Northern, and Western blots
Common questions
What happens if stringency is set too low for the intended test?+
The probe binds to sequences that are only partially complementary, producing signal at loci the probe was not designed to detect and increasing the risk of a false-positive or ambiguous result.
Why might an examiner deliberately choose low stringency?+
Low stringency conditions can be used intentionally to detect related but non-identical sequences, for example when screening for a family of similar genetic variants rather than confirming one exact match.
Related terms
- Microarray (Gene Chip / SNP Chip)
- A solid-phase hybridisation platform carrying thousands to millions of oligonucleotide probes at spatially registered positions. Hybridisation of a labelled target simultaneously queries...
- Minisatellite (VNTR)
- A hypervariable genomic locus characterised by tandem repeats of a 10-60 bp core sequence, with the number of repeat units varying between...
- Molecular Hybridisation
- The formation of a double-stranded nucleic acid molecule from two complementary single strands, driven by hydrogen-bond formation between base pairs (A-T, G-C...
- mRNA Body-Fluid Profiling
- The RT-PCR-based descendant of Northern blotting: tissue-specific messenger RNA transcripts are reverse-transcribed and amplified from crime-scene stains to identify body fluid of...
- Southern Blot
- A technique (E.M. Southern, 1975) in which restriction-digested DNA fragments are separated by gel electrophoresis, transferred to a membrane, and hybridised with...
- Western Blot (Protein Immunoblot)
- SDS-polyacrylamide gel electrophoresis (SDS-PAGE) of proteins followed by electrotransfer to a PVDF or nitrocellulose membrane, then antibody-based detection of a specific protein...