A DNA-Origami Chip Platform for Label-Free SNP Genotyping Using Toehold-Mediated Strand Displacement

Single-nucleotide polymorphisms (SNPs) are the most abundant genetic variations in the human genome [1] and hold great promise as disease-associated biomarkers.[2] There have been a variety of SNP genotyping methods, including primer extension, hybridization, ligation, and enzymatic cleavage with optical or electronic readout.[3-13] Despite this, much effort has been expended recently to develop simple and effective SNP-genotyping methods, preferably free of target labeling, without the need of stringent control of assay conditions and/or tackling complex enzyme reactions. In addition, chip-based SNP genotyping methods often suffer from relatively slow kinetics and low hybridization effi ciency at heterogeneous interfaces. [14] In this paper, we report a "DNA origami"-based strategy for label-free SNP detection in homogeneous solutions ( Figure 1 ).Copyright © 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.