Accurate Zygote-Specific Discrimination of Single-Nucleotide Polymorphisms Using Microfluidic Electrochemical DNA Melting Curves

• Published in: Angewandte Chemie International Edition 2014-03, Vol.53 (12), p.3163-3167
• Main Authors: Yang, Allen H. J., Hsieh, Kuangwen, Patterson, Adriana S., Ferguson, B. Scott, Eisenstein, Michael, Plaxco, Kevin W., Soh, H. Tom
• Format: Article
• Language: English
• Subjects: Deoxyribonucleic acid; Discrimination; Diseases; DNA; DNA - chemistry; Electrochemistry; Genes; Genomics; Humans; Loci; Melting; Microfluidic Analytical Techniques - instrumentation; Microfluidic Analytical Techniques - methods; Microfluidics; molecular diagnostics; Pathology, Molecular; Polymorphism; Polymorphism, Single Nucleotide; Real time; Zygote - cytology; Zygote - metabolism
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201310059

We report the first electrochemical system for the detection of single‐nucleotide polymorphisms (SNPs) that can accurately discriminate homozygous and heterozygous genotypes using microfluidics technology. To achieve this, our system performs real‐time melting‐curve analysis of surface‐immobilized hybridization probes. As an example, we used our sensor to analyze 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 melting 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 the diagnosis of SNP‐based diseases and personalized medicine. Rapid DNA identification: A novel microfluidic electrochemical system for the detection of single‐nucleotide polymorphisms (SNPs) uses surface‐immobilized DNA probes to accurately discriminate homozygous and heterozygous genotypes using real‐time melting‐curve analysis. Two clinically relevant SNPs in the apolipoprotein E gene were characterized and all six possible ApoE allele combinations were distinguished.