Single nucleotide polymorphism genotyping using locked nucleic acid (LNA)

Locked nucleic acid (LNA^TM) is a new class of bicyclic high affinity DNA analogs. LNA-containing oligonucleotides confer significantly increased affinity against their complementary DNA targets, increased mismatch discrimination (ΔT_m) and allow full control of the melting point of the hybridization reaction. LNA chemistry is completely compatible with the traditional DNA phosphoramidite chemistry and therefore LNA-DNA mixmer oligonucleotides can be designed with complete freedom for optimal performance. These properties render LNA oligonucleotides very well suited for SNP genotyping and have enabled several approaches for enzyme-independent SNP genotyping based on allele-specific hybridization. In addition, allele-specific PCR assays relying on enzymatically-enhanced discrimination can be improved using LNA-modified oligonucleotides. The use of LNA transforms enzyme-independent genotyping approaches into experimentally simple, robust and cost-effective assays, which are highly suited for genotyping in clinical and industrial settings.