A rat genome gene chip is shown to the media by Karol Thompson, Lead Pharmacologist in the Molecular Toxicology lab at the U.S. Food and Drug Administration (FDA) headquarters in Silver Spring, Maryland, November 5, 2009. Watching on is biologist Barry Rosenzweig. Reuters Pictures 3 weeks ago

A rat genome gene chip is shown to the media by Karol Thompson, Lead Pharmacologist in the Molecular Toxicology lab at the U.S. Food and Drug Administration (FDA) headquarters in Silver Spring, Maryland, November 5, 2009. Watching on is biologist Barry Rosenzweig.