There is a new company that is using the PCA3 gene that has obtained approval in Europe. In the US there are 2 companies that have the test, Ameripath and Bostwick laboratories, currently the PCA3-plus test.

We have had a lengthy discussion about this test on another blog entry on my site.

The test works by looking at the ratio of this PCA3 RNA to the total PSA RNA that is expected to be constant.

The idea is that a higher ratio means that you are more likely to have cancer. I have found several cancers using this test as my basis for performing a prostate biopsy.
One interesting development is the change in Bostwick's interpretation of the result. Ameripath always used 35 as the "normal" cutoff, and Bostwick started at 10. Bostwick has increased the normal value of the test to 35 now.