Milestone Achieved A Year Ahead of Schedule

ST. LOUIS and RICHMOND, Calif., Jan. 12 /PRNewswire-FirstCall/ -- Sangamo BioSciences, Inc. (Nasdaq: SGMO) today announced it has reached a major production capacity milestone as part of its agreement with Sigma-Aldrich Corporation (Nasdaq: SIAL) to commercialize zinc finger nuclease reagents (ZFNs) for research applications. The milestone triggers a payment of $1.0 million to Sangamo.

"Reaching this production milestone more than one year ahead of schedule represents an important step in our plans to develop high value ZFN research reagents for our customers," said Dr. David Smoller, President of Sigma-Aldrich's Research Biotech Business Unit. "Our CompoZr(TM) ZFN platform of reagents has captured the interest of the biotechnology research community. CompoZr reagents provide researchers with the ability to target and precisely manipulate the genome of living cells, resulting in cell lines or whole organisms with defined gene deletions, insertions, or corrections. ZFNs can be designed to target any gene in any organism and used to rapidly make precise changes to a cell's characteristics. Our aim is to provide CompoZr reagents to any investigator's 'favorite gene'. As the exclusive licensee and distributor of ZFN-based reagents for research purposes, we are pleased with Sangamo's robust and scalable approach that is helping us meet the high demand for ZFN reagents."

The ability to selectively modify or control specific genes is emerging as a critical tool in modern biotechnology. Zinc finger DNA-binding proteins (ZFPs) are the dominant class of naturally-occurring transcription factors in organisms from yeast to humans. Transcription factors, which are found in the nucleus of every cell, bind to DNA to regulate gene expression. Though there are many kinds of transcription factors, only ZFPs are amenable to engineering and precise targeting to a particular gene, or genes, of interest. By engineering ZFPs that recognize a specific DNA sequence, Sangamo scientists have enabled researchers to precisely modify targeted genes and control gene expression. This technology has the potential to play a major role in bringing new discoveries in genomics to the marketplace.

"Our ZFN technology is the gold standard for genome editing in cells and whole organisms," said Edward Lanphier, Sangamo's President and CEO. "There is a growing appreciation of the numerous applications of ZFP-based reagents in functional genomics, target validation, drug discovery, process improvement in biopharmaceutical manufacturing and the generation of transgenic animals. We are delighted with the progress that has been made in our collaboration with Sigma-Aldrich. Familiarity and success with our technology at the research level should lead to commercial success in this field as well as an appreciation of the broad therapeutic uses of our technology platform."

Sigma-Aldrich's agreement with Sangamo Biosciences, initiated in July 2007, provides Sigma-Aldrich with the exclusive right to utilize Sangamo's ZFP technology to develop and commercialize products for use as research reagents and to offer services in the research field. Sigma-Aldrich's CompoZr gene-editing technology was recently recognized as one of the Top 10 Innovations of 2008 by The Scientist and was included in the magazine's inaugural list of the most outstanding products to enter the life sciences market. For more information on Sigma-Aldrich's CompoZr ZFN technology platform, visit http://www.compozrzfn.com or contact a sales representative at zfn@sial.com.

About Sigma-Aldrich

Sigma-Aldrich is a leading Life Science and High Technology company. Its biochemical and organic chemical products and kits are used in scientific and genomic research, biotechnology, pharmaceutical development, the diagnosis of disease and as key components in pharmaceutical and other high technology manufacturing. The Company has customers in life science companies, university and government institutions, hospitals, and in industry. Over one million scientists and technologists use its products. Sigma-Aldrich operates in 36 countries and has 8,000 employees providing excellent service worldwide. Sigma-Aldrich is committed to Accelerating Customer Success through Innovation and Leadership in Life Science, High Technology and Service. For more information about Sigma-Aldrich, please visit its award-winning Web site at http://www.sigma-aldrich.com.

About Sangamo

Sangamo BioSciences, Inc. is focused on the research and development of novel DNA-binding proteins for therapeutic gene regulation and modification. The most advanced ZFP Therapeutic(TM) development program is currently in Phase 2 clinical trials for evaluation of safety and clinical effect in patients with diabetic neuropathy and ALS. Other therapeutic development programs are focused on stem cell mobilization, HIV/AIDS, cancer, neuropathic pain, Parkinson's disease and monogenic diseases. Sangamo's core competencies enable the engineering of a class of DNA-binding proteins known as zinc finger DNA-binding proteins (ZFPs). By engineering ZFPs that recognize a specific DNA sequence Sangamo has created ZFP transcription factors (ZFP TF(TM)) that can control gene expression and, consequently, cell function. Sangamo is also developing sequence-specific ZFP Nucleases (ZFN(TM)) for gene modification. Sangamo has established strategic partnerships with companies outside the human therapeutic area including Dow AgroSciences, Sigma-Aldrich Corporation and several companies applying its ZFP Technology to enhance the production of protein pharmaceuticals. For more information about Sangamo, visit the company's web site at www.sangamo.com.

This press release may contain forward-looking statements based on Sigma-Aldrich's and Sangamo's current expectations. These forward-looking statements include, without limitation, references to the research and development of novel ZFNs, potential therapeutic, medical research and pharmaceutical applications of the ZFN technology and the timing of initiation of clinical trials by Sangamo. Actual results may differ materially from these forward-looking statements due to a number of factors, including technological challenges, the ability of Sangamo and Sigma-Aldrich to develop commercially viable products and technological developments by our competitors. See the SEC filings, and in particular, the risk factors described in the Annual Report on Form 10-K and most recent Quarterly Report on Form 10-Q of each of Sangamo and Sigma-Aldrich. Neither Sigma-Aldrich nor Sangamo assumes any obligation to update the forward-looking information contained in this press release.

SOURCE Sangamo BioSciences, Inc.