U.S. Introduces New DNA Standard for Ensuring Accuracy of Genetic Tests

May 20, 2015 | 2015, Blog, May

By 

www.nytimes.com

imagesWASHINGTON — The federal government opened the door to a new era of genetic medicine on Thursday by introducing a standard way to ensure the accuracy of DNA tests used to tailor treatments for individual patients.

Scientists have identified hundreds of genetic mutations that appear to increase the risk of diseases, including cancer, Alzheimer’s and cystic fibrosis. But laboratories often report different results when they analyze genes obtained from samples of the same blood or tissue, because of variations in their testing equipment and methods.

The National Institute of Standards and Technology said Thursday that it had developed “reference materials” that could be used by laboratories to determine whether their machines and software were properly analyzing a person’s genetic blueprint, or genome.

The institute disseminates such reference materials for thousands of products including steel, concrete and peanut butter. These materials are used for myriad purposes — to calibrate instruments, to make sure buildings are safe, to ensure that nutritional labels are accurate.

Laboratories can use the new DNA standard to make sure their genetic testing is accurate. If labs get the right answers for the reference material — by finding the same mutations in the same places, for example — they can be confident that their testing of patient samples is similarly accurate.

The devices used by the laboratories, known as DNA sequencers, have greatly accelerated biomedical research and discovery, allowing scientists to pinpoint mutations and devise treatments tailored to the genetic characteristics of individual patients. Such tests and treatments, developed in research laboratories, are quickly moving into the practice of medicine.

In his State of the Union address this year, President Obama announced a “precision medicine initiative” to foster the development and adoption of such customized treatments.

For $450, scientists and laboratories can now buy a vial of the reference material from the national standards institute, a unit of the Commerce Department. The material, for sale on the agency’s website, includes 10 micrograms of DNA from a Utah woman of European ancestry. That is enough for numerous tests.

“If you send a sample of blood or a tumor biopsy to different genetic testing laboratories, you can get different results,” said Marc L. Salit, the leader of a genome measurement group at the institute. “While largely in agreement, they may have significant differences. Now, for the first time, we have a standard to check the reliability and quality of gene sequencing.”

A laboratory can use the samples to demonstrate the quality of its work, and health insurance companies can have confidence in the results, increasing the likelihood that they will pay for genome-sequencing tests, Dr. Salit said. Costs have come down in recent years, he added, but it still costs about $5,000 to analyze and interpret a whole genome.

Elizabeth A. Mansfield, a geneticist at the Food and Drug Administration who supervises its work on personalized medicine, said the reference material could lead to “better instruments and better tests.” As a result, she said, “health plans may be more willing to pay for such tests.”

The F.D.A. worked with the standards institute to develop the DNA reference material, which gives regulators a new tool to assess the accuracy of tests.

“An inaccurate genome-sequencing test can lead to patients receiving the wrong diagnosis, the wrong treatment or no treatment at all, even when effective therapy is available,” said Dr. Jeffrey E. Shuren, director of the F.D.A. Center for Devices and Radiological Health. Accurate tests have become more important, he said, as treatments are increasingly based on the type of mutations detected in genetic testing.

Dr. Francis S. Collins, director of the National Institutes of Health, said that information from the tests could benefit patients in many ways. “For example,” he said, “an oncologist might use the results of a sequencing scan to choose the chemotherapy drug that is most likely to work.”

The regulation of DNA tests and technology is complicated and in flux.

One agency, the Centers for Medicare and Medicaid Services, regulates and certifies clinical laboratories under a 1988 law. The F.D.A., a sister agency in the same department, regulates manufacturers and has authority over the actual tests. The food and drug agency has historically refrained from enforcing some of its requirements for “laboratory-developed tests,” including many genetic tests, but it proposed to overhaul and tighten regulation of these products last year.

The new reference material is for tests that use advanced technology — “next-generation sequencing” — to analyze a person’s DNA. Such tests are generally interpreted by doctors or genetic counselors and not sold directly to consumers.

In 2013, the food and drug agency told a Silicon Valley company, 23andMe, to stop selling health information reports that interpreted a person’s DNA. In February, it allowed the company to offer a direct-to-consumer test to help identify carriers of a gene linked to a specific rare disorder, Bloom syndrome.

The food and drug agency, expecting a wave of new technology to analyze the human genome, helped finance the work of scientists and engineers at the standards institute in Gaithersburg, Md.