Gene Chips Advance Medical Research

Article excerpt

Byline: Joyce Howard Price, THE WASHINGTON TIMES

Gene chips, DNA scanning devices that can sort millions of fragments of genetic information, are a major advance in personalizing disease diagnoses and medical treatments, based on differences in each patient's genes.

The thin glass chips, widely used in research laboratories for the past five years, may be commonplace in clinical practice in the not-too-distant future. They allow scientists to analyze thousands of human genes or gene fragments at once, rather than individually, so disease causes can be identified and therapies quickly applied.

Now some American scientists who have been on the cutting edge of this technology say it's time to develop international standards for the use of the tools, also known as DNA microarrays.

Last month, more than 40 scientists, including some from the U.S. Department of Health and Human Services and several from Europe and Asia, met in Paris to brainstorm this issue.

"International standardization has to happen. If not, it will hold back modern medicine, because all medical research is focused on using genomic tools for early diagnosis and treatment," said Dietrich Stephan, director of the neurogenomics division at the nonprofit Translational Genomics Research Institute, or TGen, in Phoenix.

Mr. Stephan said he is taking that position, even though the "vast majority of gene-chip use [to date] has been as a research tool," rather than in clinical practice.

He predicts global standards for assessing the technical performance of these chips will be in place in a year or two.

Janet Warrington, vice president of emerging markets and molecular diagnoses at Affymetrix, Inc., a Santa Clara, Calif.-based firm that has been a leader in gene-chip research, believes that prediction is entirely possible.

Reasons for optimism

"This is a force that's happening now. There are standard controls in development now, and it's an international effort," said Ms. Warrington, who organized and chaired the meeting in Paris.

Ira Lubin, a geneticist at the federal Centers for Disease Control and Prevention in Atlanta, who also attended the meeting, said in an interview there are "many reasons to be very optimistic" about the outlook for clinical effectiveness of DNA microarrays, based "on the work that already has been done." He termed the time frame Ms. Warrington and Mr. Stephan suggested for international standards to be in place "quite reasonable."

Officials of Affymetrix, co-developers of a DNA microarray test that's been approved by the U.S. Food and Drug Administration, identified two international organizations - the Organization for Economic Cooperation and Development (OECD) and the Clinical and Laboratory Standards Institute (CLSI) - involved in this movement.

Relapse predicted, avoided

CLSI, a nonprofit group, is "at work designing a clinical protocol," Ms. Warrington said in a telephone interview.

Mr. Stephan and other researchers atTGen have used gene chips to help determine the chances of relapse in children whose leukemia is in remission and to help select the best therapies for other cancer patients.

Mr. Stephan cites one man who, three years ago, was "on his deathbed with pancreatic cancer," one of the deadliest forms of cancer. By monitoring the patient's gene activity with DNA chips, Mr. Stephan said, it appeared he could benefit from a drug commonly used to treat breast cancer. The patient was put on that regimen.

"Today, he is healthy as a horse," the researcher said.

Ethical issues possible

No one is saying DNA-based medical testing is always so beneficial. Research is still under way to determine its effectiveness, and, increasingly, it's being tested in clinical trials.

"The bottom line is that we want to ensure that there is an appropriate level of quality" in DNA-based medical testing, as in other medical testing, said Mr. …