Genzyme Molecular Oncology announced that the United States Patent Office has issued Patent No. 6,498,013 covering its powerful LongSAGE technology. The patent covers the dynamic gene expression method that is an expansion of the previously patented Serial Analysis of Gene Expression, or SAGE, technique. LongSAGE is regarded as a significant advance that allows for the matching of expression data directly with genomic information, enabling the rapid identification of novel genes.

"This patent broadens our SAGE portfolio and confirms the uniqueness of SAGE in the identification and measurement of gene expression," stated Gail Maderis, president of Genzyme Molecular Oncology. "We are now performing the majority of our SAGE analysis with this enhanced method. Combining LongSAGE data with our existing SAGE database has accelerated our identification of novel cancer targets. We are very excited about its future use."

The LongSAGE method is utilized by Genzyme Molecular Oncology in both its antigen discovery and antiangiogenesis programs. The SAGE methods all offer high-efficiency means of comprehensively identifying and quantifying genes being expressed in a particular tissue or cell at a given time. A large group of academic and commercial researchers are using SAGE techniques to validate data outlined in the sequencing of the genome, and to better understand the set of instructions carried by genes to create proteins that regulate most biological activities in the body.

The LongSAGE method utilizes a 'tag' from each expressed transcript of about 20-22 base pairs in length. These tags provide a unique identifier for each transcript, similar to a bar code. Each LongSAGE tag is usually found to occur uniquely in the genome, so by matching a LongSAGE tag to human genome data, it is often possible to identify the location of genes.

LongSAGE is also superior to previous methods of genome mining because it is based on a sampling of biological material and is able to recognize genes that may be missed by the existing computer algorithms. By not excluding unusual genetic patterns, a number of previously unrecognized genes can be identified or confirmed. LongSAGE provides data on which of these genes may be important in physiological or disease pathways.

In addition to the 38,000 genes confirmed by the Human Genome Project to date, public and private gene sequencing efforts have identified some 15,000 sequences that meet strict criteria for genes but have not been confirmed as such, and have made another 10,000 to 20,000 gene predictions of lower confidence.