PROGENSA(R) PCA3 Assay Can Help Guide Repeat Prostate Biopsy Decisions, Data Presented at Leading Medical Meeting Confirm

More Than 2,400 Men Tested in Largest Studies to Date of Gen-Probe's Molecular Urine Test -

SAN DIEGO, March 8, 2010 - Gen-Probe's (Nasdaq: GPRO) PROGENSA(R) PCA3 assay can help determine
whether men suspected of having prostate cancer should undergo a repeat
biopsy, according to data from the two largest studies to date of the
molecular urine test. The studies were presented last week at the American
Society of Clinical Oncology's (ASCO) Genitourinary (GU) Cancers Symposium in
San Francisco.

"These two studies, which involved more than 2,400 men, are the most
significant conducted thus far of our PROGENSA PCA3 molecular urine test, and
confirm the assay's ability to predict the outcome of a repeat prostate
biopsy, thereby helping physicians provide more appropriate, personalized
patient care," said Eric Lai, PhD, Gen-Probe's senior vice president of
research and development.

In the studies presented at the ASCO GU meeting, PCA3 was used to test
urine samples from men enrolled in the REDUCE trial of GlaxoSmithKline's drug
dutasteride. PCA3 testing was done on urine samples from 1,140 men in the
placebo arm of the REDUCE trial, and from 1,308 men in the dutasteride arm.
All men underwent prostate biopsies two and four years after enrollment.

The first PCA3 study presented at the meeting originated from the placebo
arm of the REDUCE trial. This study, which was highlighted in ASCO's official
press program, showed that PCA3 scores were significantly correlated with a
positive prostate biopsy result (P<0.0001), and that men who had higher PCA3
scores were more likely to have prostate cancer. Specifically, cancer was
diagnosed in only 6% of men with very low PCA3 scores, but in 57% of men with
very high PCA3 scores.

PCA3 scores also correlated with cancer aggressiveness: median PCA3
scores were higher in men with high-grade cancers than in those with
low-grade cancers (P=0.0017). Finally, the PCA3 test also predicted the
likelihood of a prostate cancer diagnosis on a future biopsy. Specifically,
men with elevated PCA3 scores and negative biopsies at the two-year mark were
twice as likely as men with lower PCA3 scores and negative biopsies to have
cancer detected at the four-year mark (P=0.0002).

The second PCA3 study presented at the ASCO GU meeting originated from
the dutasteride arm of the REDUCE trial. This study, which was selected for
oral presentation at the meeting, showed that PCA3 also can be used to
predict prostate biopsy outcomes in men taking dutasteride. In contrast to
serum PSA testing, median PCA3 scores were equivalent in the placebo and
dutasteride groups, and PCA3 sensitivity and specificity were also similar
between the two groups.

The second study also confirmed earlier research that showed PCA3
outperforms serum PSA testing for prostate cancer detection, and improves
diagnostic accuracy when combined with serum PSA testing and other clinical
information.

About Prostate Cancer and PCA3

According to the European Prostate Cancer Coalition, prostate cancer is
one of the most common men's cancers in Europe. More than 300,000 new cases
of prostate cancer are diagnosed annually in the European Union, and more
than two million Europeans are living with the disease.

PCA3 is a gene that is highly over-expressed in more than 90% of prostate
cancers, and that can be quantified in urine specimens following a digital
rectal examination. Studies have shown that because PCA3 is highly specific
for prostate cancer, it predicts the results of repeat biopsies more
accurately than traditional prostate-specific antigen (PSA) testing.

Gen-Probe's PROGENSA(R) PCA3 assay, which has been CE-marked for sale in
the European Union, is the first urine-based molecular diagnostic assay for
prostate cancer. In August of 2009, Gen-Probe initiated a clinical trial
intended to secure U.S. regulatory approval of the assay for use on its
semi-automated instrument system. The Company remains on track to file a
Premarket Approval Application later this year.

Data from approximately 30 peer-reviewed publications suggest that the
PROGENSA PCA3 assay, when used with other patient information, may help
address some of the well-known challenges urologists face when identifying
prostate cancer, such as minimizing unnecessary biopsies.

About Gen-Probe

Gen-Probe Incorporated is a global leader in the development, manufacture
and marketing of rapid, accurate and cost-effective molecular diagnostic
products and services that are used primarily to diagnose human diseases,
screen donated human blood, and ensure transplant compatibility. Gen-Probe
has approximately 27 years of NAT expertise, and received the 2004 National
Medal of Technology, America's highest honor for technological innovation,
for developing NAT assays for blood screening. Gen-Probe is headquartered in
San Diego and employs approximately 1,300 people. For more information, go to
www.gen-probe.com.

Caution Regarding Forward-Looking Statements

Any statements in this press release about Gen-Probe's expectations,
beliefs, plans, objectives, assumptions or future events or performance are
not historical facts and are forward-looking statements. These statements are
often, but not always, made through the use of words or phrases such as
believe, will, expect, anticipate, estimate, intend, plan and would. For
example, statements concerning new products, potential regulatory approvals,
customer adoption, and results of future clinical studies are all
forward-looking statements. Forward-looking statements are not guarantees of
performance. They involve known and unknown risks, uncertainties and
assumptions that may cause actual results, levels of activity, performance or
achievements to differ materially from those expressed or implied. Some of
the risks, uncertainties and assumptions that could cause actual results to
differ materially from estimates or projections contained in the
forward-looking statements include but are not limited to: (i) the risk that
results from the US clinical trial of our PCA3 test will not be favorable;
(ii) the risk that our PCA3 test will not be approved by FDA for marketing in
the US in the timeframes we expect, if at all; (iii) the possibility that the
market for the sale of our PCA3 product may not develop as expected; (iv) the
risk that we may not be able to compete effectively with other tests for
prostate cancer; (v) the risk that we may not be able to maintain our current
exclusive license concerning PCA3; and (vi) the risk that our third party
distributors may not distribute our products effectively. The foregoing
describes some, but not all, of the factors that could affect our ability to
achieve results described in any forward-looking statements. For additional
information about risks and uncertainties Gen-Probe faces and a discussion of
the Company's financial statements and footnotes, see documents filed with
the SEC, including the most recent annual report on Form 10-K and all
subsequent periodic reports. We assume no obligation and expressly disclaim
any duty to update any forward-looking statement to reflect events or
circumstances after the date of this news release or to reflect the
occurrence of subsequent events.

    Contact:
    Michael Watts
    Vice president, investor relations and
    corporate communications
    +1-858-410-8673

Michael Watts, Vice president, investor relations and corporate communications of Gen-Probe, +1-858-410-8673