Highly sensitive PNA Array Platform Technology for Single Nucleotide Mismatch Discrimination

Reliable discrimination of single nucleotide mismatch was demonstrated using arrays with peptide nucleic acid (PNA) probes. Newly developed PNA probes immobilization method and hybridization conditions for PNA arrays gave excellent specificity and sensitivity. And we compared the specificity, sensitivity, and stability obtained with the PNA and DNA arrays in discriminating single nucleotide mismatches. PNA arrays had superior perfect match-to-mismatch signal ratios and sensitivities. The relative signal intensities of mismatch PNA probes ranged from 1.6% to 12.1% of the perfect match PNA probes. These results demonstrated that the PNA arrays were 2.0 to 37.3 times more specific and about 10 times more sensitive than DNA arrays. A PNA array showed the same specificity and sensitivity after 12-month storage at room temperature.