Lab on a Swab

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So far, the Genotyper has been tested on human genes, mice (a common source for searching out genetic variations), and on the DNA in two strains of influenza.

"You have a sort of microprocessor, or hardware piece," says original group member Mark A. Burns, professor of chemical and biomedical engineering at the University of Michigan. "Then you just put on different software, but in our case you would call it wetware, different reagents, to do tests of different things."

The Michigan researchers have not gone through the process with a throat sample because they need to solve the purification issue (see Notebook). Thus far, they've taken pre-purified DNA and genotyped it.

Although it's been 36 years since the last worldwide influenza pandemic in the human population, the threat of a contemporary outbreak is always present. Recent outbreaks of avian influenza underline that reality. Furthermore, because of its genetic mutability, rapid transmission, and ability to move from animal to human, the need to track new variants of the flu virus is critical. According to William A. Petri Jr., professor of medicine, microbiology, and pathology at the University of Virginia, virtually all flu experts agree that another influenza pandemic will occur.

As a physician, Petri envisions a Genotyper-like device being used some day to quickly identify the type, subtype, or strain of the influenza virus in a patient, and then a doctor using the information to select the appropriate drug.

Petri notes that most patients today wait two to three days before visiting the doctor. If they were able to diagnose themselves at home within the critical 48-hour period, they could get more effective treatment -- and decrease the chances of infecting others.

In 15 to 20 years, researchers hope that a patient can take a nasal swab or throat sample, put it on the Genotyper chip, and self-diagnose their condition at home. Then data could be entered into a wireless network and variants of the flu mapped neighborhood by neighborhood, city by city, or beyond.

Burns envisions a half-dozen other possible uses for such a genetic-detecting integrated device (see Notebook). But he also acknowledges that there's the potential for the technology to be abused. Unscrupulous health insurers or potential employers, for instance, could intercept information about an individual's genetic make-up and discriminate against policy-holders or employees. 

But how feasible is such a revolutionary diagnostic device?

"Getting something like this to really work at a commercial level involves many things, not only technologically, but also sociologically, economically," says Larson. Despite these caveats, though, he thinks it could become mass produced and inexpensive.

"What we're really trying to do is prod the field forward and focus on what we see as a big need for tracking viral pathogens," Larson says.