Detecting mutations

A new method to identify DNA mutations may shepherd in an era of small, portable, electronic devices for the rapid screening and identification of genes that harbour disease.

Joseph Wang, director of the Center for Bioelectronics and Biosensors at the Biodesign Institute at Arizona State University (ASU), led a team that successfully merged efforts in the fields of biosensors, electronics, and nanotechnology to fashion nanocrystals that can act as "DNA biosensors" by electronically recognising subtle mutations in the DNA. This creates enormous potential for applications such as the diagnosis and treatment of genetic diseases, detection of infectious agents and reliable forensic analysis.

"The ultimate goal is to make something similar to a hand-held glucose monitor for future genetic testing," Wang says. "The electronic detection of DNA is a thing of beauty. You can make it small, low-power, inexpensive and robust, creating all sorts of advantages."

Among the keys to unearthing the mysteries behind individual genetic variation and diseases like cancer are fine differences – single nucleotide polymorphisms, or "SNPs" – buried within the three billion chemical bases of DNA comprising the human genome. Not every SNP found will necessarily cause a mutation or determine our eye or hair colour but, on average, SNPs occur about once in every 1,000 DNA bases, adding up to 3 million potential individual differences across the human genome. Wang's method allows for an accurate, ultra-sensitive, rapid and low-cost identification of these SNP variants.