When you're sick and go to the doctor, frequently the doctor will stick you with a needle, draw some blood, and use that to help diagnose your problem. Rose Hoban reports on new research that might make some of those painful needle pricks a thing of the past.


James Melvin is a dental researcher at the University of Rochester, and he's been looking into the use of saliva as a way to diagnose disease. "They are using saliva for some tests right now," he says, pointing to the standard test for HIV.


Melvin says he thinks the proteins in saliva could be used as markers for other diseases, as well, the same way proteins in blood are. He and his colleagues went looking for proteins in saliva.


"One of the things that we knew at the beginning of this study was that there are about 75 or 80 proteins that were really abundant," Melvin explains, adding that they have been studied a lot over the last several decades. "But they are so abundant that it [was] difficult to look at the less abundant ones that are more important in terms of disease biomarkers, probably because they're the ones that reflect things that got from the blood into the saliva."


Melvin and his colleagues used sophisticated technology to separate out all the different proteins in saliva.


First, they found there were many more proteins in saliva than originally thought ?about a thousand different ones. Then they found that, indeed, some of the proteins present in saliva could indicate the presence of disease.


"There are things associated with different forms of cancer, diabetes, cardiovascular disease," Melvin explains, "so basically any disease that they monitor [in] blood? you can do the same thing in saliva."


Melvin cautions that this research is still early and that low-cost and efficient techniques still need to be devised to do testing with saliva. But he says the technique should be available in the next decade or so.

His research appears in the Journal of Proteome Research.