Sanger Institute Selects Ventana's DISCOVERY System as the IHC Platform Technology for the Atlas Project.

Business Editors/Health/Medical Writers

TUCSON, Ariz.--(BUSINESS WIRE)--March 25, 2003

Ventana Medical Systems Inc. (Nasdaq: VMSI) today reported that the Sanger Institute (Cambridge, United Kingdom) has purchased Ventana's DISCOVERY(TM) system immunohistochemistry platform for use in its Atlas Gene Expression Project. The Sanger Institute will be installing multiple DISCOVERY(TM) systems in its Cambridge research facilities.

The Immunocytochemistry sub-group, led by Tony Warford, will introduce the use of tissue micro-arrays and automated immunocytochemical staining to the Sanger Institute. As well as developing and implementing protocols for automated staining using recombinant antibodies, the group will develop methods for automated data collection and interpretation. It is anticipated that the project will add value to this tissue profiling using a variety of specialized immunocytochemical procedures. Ultimately the group will generate reports on expression of individual proteins and use these, along with associated electronic images, to populate a relational database.

Christopher Gleeson, president and CEO of Ventana Medical Systems Inc., commented, "We are delighted that an institute with the stature of Sanger has chosen our DISCOVERY(TM) system to help with this cutting-edge research initiative. Additionally, we are very excited at the opportunity to be working with Sanger's research groups on certain development projects that will enhance the Discovery's capabilities in the immunohistochemistry area."

Ventana develops, manufactures and markets instrument/reagent systems that automate tissue preparation and slide staining in clinical histology and drug discovery laboratories worldwide. Ventana's clinical systems are important tools used in the diagnosis and treatment of cancer and infectious diseases. Ventana's drug discovery systems are used to accelerate the discovery of new drug targets and evaluate the safety of new drug compounds.

The news release contains certain forward-looking statements within the meaning of the federal securities laws. These forward-looking statements include, but are not limited to, statements regarding our ability to grow sales, the anticipated market impact of our R&D efforts, our ability to manage costs, sustain profits and general financial performance expectations. Investors are cautioned that all forward-looking statements involve risks and uncertainties that could cause actual results to differ, perhaps materially, from those anticipated or suggested by such forward-looking statements. These risks and uncertainties include, without limitations, risks associated with market acceptance of new automated histology products, continued success in asset management, continued improvements in our manufacturing efficiencies, on-schedule launches of our new products, currency exchange rate variability, competition and competitive pressures on pricing and general economic conditions in the United States and in the regions served by Ventana, and those risk factors contained in our periodic reports including Form 10-K for the year ended Dec. 31, 2002, and all other Securities and Exchange Commission (SEC) filings. Copies of filings made with the SEC are available through the SEC's electronic data gathering analysis retrieval system (EDGAR) at www.sec.gov. We undertake no obligation following the date of this release to update or revise our forward-looking statements or to update the reasons actual results could differ materially from those anticipated in forward-looking statements. We caution you not to place undue reliance upon any such forward-looking statements, which speak only as of the date such statements are made. We cannot guarantee any future operating results, activity, performance or achievement.

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