Saliva Tests Making Their Way to Routine Care

Screens are already in the works for cancer, other illnesses, experts say.

By Alan Mozes
HealthDay Reporter
Thursday, March 22, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

THURSDAY, March 22 (HealthDay News) -- Simple, cheap diagnostic tests based on the analysis of saliva are within spitting distance of development, says a consortium of American researchers.

Scientists say the novel protocol could be available as a standard of care as early as 2011 to screen for a variety of major diseases.

"The ability to detect and monitor diseases through noninvasive means is a highly desirable goal in health care," said Dr. David T. Wong, director of the Dental Research Institute at the University of California, Los Angeles. "Saliva, a totally noninvasive fluid, holds this ability but is not currently used in (the) mainstream. All of this is just about to change."

Wong was scheduled to describe the new tests Thursday at the International Association for Dental Research annual meeting, in New Orleans.

To develop the saliva-based screens, Wong has teamed up with researchers at the U.S. National Institute of Dental and Craniofacial Research; the University of California, San Francisco; and the Scripps Research Institute.

Together, the team is engaged in a painstaking mapping of so-called "diagnostic alphabets" present in saliva. Identifying the components of such alphabets is key to "reading" the signs of disease.

So far, two such alphabets are substantially decoded: one based on salivary proteins and another based on salivary messenger RNAs (mRNA) -- molecules integral to the formation of proteins.

More than 1,500 salivary proteins have been identified, the authors noted, alongside about 3,000 mRNAs.

Based on their detective work, Wong's group announced that their research has already uncovered indicators pointing the way toward diagnosing both oral cancer and an autoimmune illness called Sjogren's syndrome.

He noted that oral cancer can be identified in saliva by screening for five specific proteins and four mRNAs that form a unique diagnostic signature in more than 90 percent of cases.

Similarly, a small subset of proteins and mRNAs appears to serve as markers for Sjogren's syndrome.