Gen-Probe Completes Acquisition of Tepnel Life Sciences

SAN DIEGO - - Transaction Brings Growth Opportunities in Transplant Diagnostics, Genetic Testing and Pharmaceutical Services, Accelerates European Expansion Strategy –

Gen-Probe (Nasdaq: GPRO) announced today that the Company has completed its acquisition of Tepnel Life Sciences, plc, a rapidly growing molecular diagnostics and pharmaceutical services company based in the United Kingdom, for 27.1 pence (US$0.40)(1) per share, or approximately 92.8 million pounds sterling (US$136.4 million) in total.

“We believe this acquisition brings Gen-Probe new growth opportunities in transplant diagnostics, genetic testing and pharmaceutical services, and also accelerates our European expansion strategy,” said Carl Hull, Gen-Probe’s president and chief operating officer. “We are very pleased to close the transaction and are ready to work with our new employees and customers to enhance their already strong molecular diagnostics and pharmaceutical services businesses.”

The transaction, which was structured as a “scheme of arrangement” under English law, was supported by more than 99% of Tepnel shareholders. The scheme became effective today following confirmation by the High Court of Justice in England and Wales and the registration of the Court documents. In addition, Tepnel’s listing on the Alternative Investment Market (AIM) operated by the London Stock Exchange was canceled today. Cash consideration will be sent to Tepnel’s shareholders within 14 days.

As previously disclosed, Gen-Probe is financing the acquisition via a revolving credit facility that bears interest at a floating rate 0.6 percent above the one-month London Interbank Offered Rate (LIBOR), which was recently 0.5 percent.

On a non-GAAP basis, Gen-Probe anticipates the transaction will be neutral to the Company’s 2009 earnings per share (EPS), and accretive to its 2010 EPS. Gen-Probe expects to update its 2009 financial guidance to include the effects of the acquisition in its first quarter earnings release on April 30.

About Non-GAAP Financial Measures

This announcement contains certain financial measures that are not calculated in accordance with U.S. GAAP, including non-GAAP EPS. Non-GAAP EPS excludes all non-cash charges such as intangible amortization and stock compensation expense, as well as transaction expenses. Gen-Probe’s management believes these U.S. non-GAAP financial measures provide Gen-Probe investors meaningful supplemental information regarding the expected financial results of the acquisition.

Tepnel has not reconciled its historical financial statements to U.S. GAAP. All pro forma combined financial information in this press release is based upon a combination of Gen-Probe historical and projected financial information, prepared in accordance with U.S. GAAP, and Tepnel’s historical and projected financial information, prepared in accordance with International Financial Reporting Standards (IFRS). Based on Gen-Probe’s preliminary analysis, the Company does not anticipate material adjustments to reconcile U.S. GAAP with IFRS.

About Gen-Probe

Gen-Probe Incorporated is a global leader in the development, manufacture and marketing of rapid, accurate and cost-effective nucleic acid tests (NATs) that are used primarily to diagnose human diseases and screen donated human blood. Gen-Probe has more than 25 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 1,200 people. For more information, go to www.gen-probe.com.

Caution Regarding Forward-Looking Statements

Any statements in this news release relating to 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 the expected benefits of the proposed acquisition and expected financial results 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 these risks, uncertainties and assumptions include but are not limited to: (i) the risk that Gen-Probe will not successfully integrate Tepnel or achieve expected strategic or financial benefits, (ii) the risk that facts relating to Tepnel that may affect strategic and other benefits of the acquisition may be unknown to Gen-Probe, and (iii) the risk that Gen-Probe may not achieve its expected 2009 growth, revenue, earnings or other financial targets that are assumed in its accretion analysis. The foregoing list sets forth some, but not all, of the factors that could affect the Company’s ability to achieve results described in any forward-looking statements. For additional information about risks and uncertainties Gen-Probe faces and a discussion of its 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. Gen-Probe assumes no obligation and expressly disclaims any duty to update forward-looking statements to reflect events or circumstances after the date of this news release or to reflect the occurrence of subsequent events.

(1) In this press release, British pounds are converted into U.S. dollars at yesterday’s approximate exchange rate of 1 pound to $1.47.

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

Source: Gen-Probe Incorporated

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