By Randall Osborne

Adding to the list of collaborators in its homologous recombination program, Lexicon Genetics Inc. began with Genetics Institute Inc. (GI) a multi-year pact, under which Lexicon will provide up to 30 lines of knockout mice to specified gene targets.

"Is this a $300 million positional cloning deal? No," said Arthur Sands, president and CEO of The Woodlands, Texas-based Lexicon. "But it's another piece of our story."

Although financial terms were not disclosed, the latest "piece" is worth up to $4.5 million, based on the going rate for knockout mice, which is $100,000 to $150,000, Sands said. GI, which did not disclose the proprietary genes to be used as targets, is a wholly owned subsidiary of Madison, N.J.-based American Home Products Corp.

Last April, privately held Lexicon, which was founded in 1995, signed its first partner, the non-profit Merck Genome Research Institute, of West Point, Pa., which agreed to pay Lexicon $8 million over five years to make 150 new mouse models. (See BioWorld Today, June 2, 1997, p. 1.)

In the Merck partnership, the knockout mice — engineered to carry mutant alleles of particular genes — will be distributed on a not-for-profit basis to the scientific community. They can allow researchers to learn what happens when a specific gene with a human parallel is turned off. The mice may also serve as test animals in preclinical drug trials.

Each new line of mice will have a distinct gene modification selected from OmniBank, a complete database of functional genetic information, built by Lexicon using high-throughput gene-trapping technology.

The database contains mouse embryonic stem cell clones, each with a gene trap mutation identified by sequence tags that derive from the genes that are mutated.

By September, Lexicon had delivered the first 10 mutant mouse models to Merck.

In January, Lexicon signed a deal with ZymoGenetics, a Seattle-based division of Novo Nordisk A/S, of Denmark, providing ZymoGenetics with access to the Omnibank database. Like the Merck partnership, it included 150 mice. Financial terms were not disclosed.

Lexicon is replicating not only mice, Sands said, but a non-exclusive database subscription deal that can be repeated with new customers, as Incyte Pharmaceuticals Inc., of Palo Alto, Calif., does.

"When you try to explain the value of functional genomics, it's hard to quantitate," Sands said.

He called the knockout mouse "an anonymous functional genomics package. A knockout mouse can deliver not only a gene, but a mechanism by which to explore the function. It's about 10 to 100 times more valuable. Nobody knows what the function will be." *