The Label-Free Unambiguous Detection and Symbolic Display of Single Nucleotide Polymorphisms on DNA Origami

Single nucleotide polymorphisms (SNPs) are the most common genetic variation in the genome Kinetic methods based on branch migration have proved successful for detecting SNPs because a mispair inhibits the progress of branch migration in the direction of the mispair We have combined the effectiveness of kinetic methods with atomic force microscopy of DNA origami patterns to produce a direct visual readout of the target nucleotide contained in the probe sequence. The origami contains graphical representations of the four nucleotide alphabetic, A, T, G and C, and the symbol containing the test nucleotide identify vanishes in the presence of the probe. The system also works with pairs of probes, corresponding to heterozygous diploid genomes.