Nanogen Issued Patent for Technology Enabling Assay Development to Detect Difficult Nucleic Acid Sequences

Nov 17, 2005, 00:00 ET from Nanogen, Inc.

    SAN DIEGO, Nov. 17 /PRNewswire-FirstCall/ -- Nanogen, Inc. (Nasdaq:   NGEN),
 developer of advanced diagnostic products, announced today that its
 subsidiary, Epoch Biosciences, was issued Patent No. 6,962,991, "Process for
 the synthesis of pyrazolopyrimidines" by the U.S. Patent and Trademark Office.
 The '991 patent relates to a process for the synthesis of pyrazolopyrimidine
 nucleoside phosphoramidites.  This process allows the economical production of
 these important nucleic acid building components.  The incorporation of
 pyrazolopyrimidine bases into nucleic acid probes and primers in place of the
 normal guanine (G) base allows the development of diagnostic assay reagents
 that can target sequences intractable to normal probes and primers.
     Efficient and accurate detection of nucleic acid targets play an integral
 role in infectious and genetic disease management.  Under normal
 circumstances, nucleic acid sequences that have large stretches of G residues
 have a tendency to bind together instead of binding to their complementary DNA
 strand, making those sequences extremely difficult to design assays to detect.
 Use of pyrazolopyrimidine-modified oligonucleotides can eliminate
 self-association in primers and probes with high GC-content.  This technology
 allows Nanogen to develop highly sensitive amplification-based diagnostic
 assays, solving a serious limitation in the traditional design of assays.
 Often times these intractable sequences can code for genes altered by
 mutations or changed by diseases such as cancer, so detection of molecular
 events can be critical in managing patient treatment.
     "Nanogen's technologies for molecular diagnostics uniquely position us to
 develop assays for diseases that cannot be detected by other nucleic-acid
 based technologies," noted Howard C. Birndorf, chairman and chief executive
 officer of Nanogen.  "This intellectual property distinguishes the real-time
 PCR analyte specific reagents we're developing for these unmet needs in
 diagnostics, which we'll use to secure a solid position in the rapidly growing
 molecular testing market."
     About Nanogen, Inc.
     Nanogen's advanced technologies provide researchers, clinicians and
 physicians worldwide with improved methods and tools to predict, diagnose, and
 ultimately help treat disease.  The company's products include real-time PCR
 reagents, the NanoChip(R) electronic microarray platform and a line of rapid
 diagnostic tests.  Nanogen's ten years of pioneering research involving
 nanotechnology holds the promise of miniaturization and continues to be
 supported for its potential for diagnostic and biowarfare applications.  For
 additional information please visit Nanogen's website at
     Forward-Looking Statement
     This press release contains forward-looking statements that are subject to
 risks and uncertainties that could cause actual results to differ materially
 from those set forth in the forward-looking statements, including whether
 patents owned or licensed by Nanogen will be developed into products, whether
 the patents owned by Nanogen offer any protection against competitors with
 competing technologies, whether products under development can be successfully
 developed and commercialized, whether results reported by our customers or
 partners can be identically replicated, and other risks and uncertainties
 discussed under the caption "Factors That May Affect Results" and elsewhere in
 Nanogen's Form 10-K or Form 10-Q most recently filed with the Securities and
 Exchange Commission.  These forward-looking statements speak only as of the
 date hereof.  Nanogen disclaims any intent or obligation to update these
 forward-looking statements.

SOURCE Nanogen, Inc.