What you should know about Locked Nucleic Acids®
Are you in need of a qPCR probe? Do you have complex targets and very small gene fragments?
With Locked Nucleic Acids (LNA®), you CAN use a shorter probe in your assay and expect greater sensitivity and discrimination for your gene target.
Dr. Ashley Heath of the Sigma Custom Products Technical Service team tells us below about the details of this novel alternative to standard DNA probe chemistries.
What are locked nucleic acids (LNA®)?
LNA® is a novel type of nucleic acid analog that contains a 2’-O-4’-C methylene bridge.
This oligo modification
- Confers greater thermal stability
- Reduces its flexibility
- Increases hybridization interactions of the base.
A comparison of LNA® to DNA is shown below.
I use dual-labeled fluorescent probes (DLFPs). What’s the difference?
DLFPs contain DNA monomers and are generally 25-35 bases in length. LNA® probes contain a mixture of DNA and LNA® monomers and are generally 14-17 bases in length.
Do I need to alter my protocol to use LNA® based probes?
No. LNA® probes are hydrolysis probes like DLFPs. Experimental set up and data collection are the same.
What are there advantages to using LNAs®?
LNA® probes have a greater thermal stability compared to conventional DNA or RNA. Additionally it is possible, with strategic placement of the LNA® bases, to optimize the Tm level and hybridization specificity.
Incorporating LNA® chemistry into your qPCR probes can improve performance in SNP discrimination, multiplex assays and when working with problematic target sequences.
Read the full list of LNA® FAQs
Dr. Heath and his fellow technical service team are available to answer your toughest questions AND to provide FREE qPCR primer and probe design. The team uses Beacon Designer to routinely provide design for primers and a variety of probes including dual labeled probes, LNA® probes, Molecular Beacons, Scorpions™ and LightCycler® probes. Now that’s service!
Experienced technical support is just a phone call away or visit sigma.com/designmyprobe to submit your design request.
Dr. Heath (Senior Technical Service Scientist) has extensive experience both in academic research and in the life sciences industry. He holds a D.Phil. degree from the University of Sussex, England, in Physiology and Anatomy, and has continued education in Infectious Diseases from the London School of Hygiene and Tropical Medicine. Prior to joining SIGMA in 1996, he held faculty positions at the Pennsylvania College of Optometry, Philadelphia, PA. and at Baylor College of Medicine, Houston, TX. At SIGMA he has worked in the areas of R&D, technical sales and support, and business development.
**LNA® oligonucleotides produced under license from Exiqon A/S.
