Bi-allelic SNP genotyping using the TaqMan® assay.

With TaqMan(®) technology allele-specific probes are utilized for quick and reliable genotyping of known polymorphic sites. TaqMan assays are robust in genotyping multiple variant types, including single nucleotide polymorphisms, insertions/deletions, and presence/absence variants. To query a single bi-allelic polymorphism, two TaqMan probes labeled with distinct fluorophores are designed such that they hybridize to different alleles during PCR-based amplification of a surrounding target region. During the primer extension phase of PCR, the 5'-3' exonuclease activity of Taq polymerase cleaves and releases the fluorophores from bound probes. At the end of PCR, the emission intensity of each fluorophore is measured and allele determination at the queried site can be made.