LCR (Ligase Chain Reaction) is a method similar to PCR (Polymerase Chain Reaction) that amplifies DNA and has promising diagnostic applications. LCR is a ligation-dependent method that can distinguish between DNA sequences differing in by only one nucleotide (SNPs). Four probes are used in LCR, one pair complementary to each strand in the target sequence, with the ligation junction at the SNP to be discriminated. The method uses thermostable DNA ligases such as Taq DNA Ligase (NEB #M0208) and 9°N™ DNA Ligase(NEB #M0238).

For more information regarding ligase specificity and high fidelity ligases, visit “Substrate specificity and mismatch discrimination in DNA ligases”.