Accurate Zygote-Specific SNP Discrimination Using Microfluidic Electrochemical DNA Melt Curves

We report the first electrochemical SNP detection system that can accurately discriminate homozygous and heterozygous genotypes using microfluidics technology. To achieve this, our system performs real-time melt-curve analysis of surface immobilized hybridization probe. As an example, we used our sensor to genotype two SNPs in the apolipoprotein E (ApoE) gene, where homozygous and heterozygous mutations greatly affect the risk of late-onset Alzheimer’s disease. Using probes specific for each SNP, we simultaneously acquired melt curves for probe-target duplexes at two different loci and thereby accurately distinguish all six possible ApoE allele combinations. Since the design of our device and probes can be readily adapted for targeting other loci, we believe that our method offers a modular platform for SNP-based disease diagnosis and personalized medicine.