March 2000 News

New Center Uses Gene Chips to Test Potential Toxins

March 16, 2000

The National Institute of Environmental Health Sciences (NIEHS) has created a $500,000 Microarray Center at its laboratories in North Carolina that will help evaluate the toxicity of chemicals without animal testing.

The new center uses the ToxChip, developed at NIEHS, which contains copies, or clones, of about 2,000 of the 80,000 genes in the human body. It will also use the Human ToxChip, an even newer microarray containing clusters of each of 12,000 different cloned genes.

Toxic substances produce changes that express genes-- turn them on and off. By observing how toxic chemicals turn "on" or "off" the cloned genes, researchers can evaluate the potential effects of the substances on humans.

The center is first evaluating known toxins to build a database showing the typical genetic changes these poisons produce. Once they have "signature profiles" of the known toxins, the scientists can evaluate other chemicals for potential harm by comparing the gene changes they produce with those made by the known toxins.

"The idea is simple," says NIEHS Director Kenneth Olden. "If ToxChip screening shows that a test chemical changes key gene expression in the same way as a known toxin does, there's a strong likelihood the test chemical may be harmful too."

The Microarry Center could provide safety information better and faster than do animal tests-and it may replace, augment, or improve on many of them.

For more details go here.