Before the Supreme Court ruled Thursday that companies cannot own exclusive rights to human genes, leukemia patients at NewYork-Presbyterian Hospital often waited days for the blood test results that might tell them how long they could expect to live. Now, doctors at that hospital say they are free to perform the genetic test in-house, which would make it faster and cheaper and could potentially extend the lives of patients.

Supreme Court says human genes are not patentable

That FLT3 gene test for leukemia, though not at issue in the Supreme Court case, is just one of many DNA tests that could become more accessible and less expensive as doctors and other companies gain the ability to offer them without infringing on patents, medical experts say.

“The gene patents were literally putting people’s lives at risk, because you’d have to wait till one company could do the testing, whereas I could do it in my own lab in three hours,” says Christopher Mason, a biophysics professor at Cornell who also works at the university-affiliated New York-Presbyterian Hospital. Because the leukemia gene was patented by Invivoscribe Technologies, doctors have had to send patients’ blood to the company’s San Diego-based lab to test it.

Invivoscribe, however, says its San Diego clinic is the only lab licensed to do the FLT3 test for patients in all 50 states, and the company does not believe the court’s ruling affects its practices or business. According to Invivoscribe CEO Jeffrey Miller, the company’s patents do not make claims to the FLT3 gene itself, “and none of them have been weakened by the Supreme Court decision.” Invivoscribe’s patents relate to methods of testing for particular mutations in the FLT3 gene, Miller wrote: “The presence or absence of these mutations is critical to direct proper treatment of patients with acute myeloid leukemia, AML.” Still, he adds, Invivoscribe’s test is “extraordinarily fast,” providing results faster than local labs, and would not delay a patient’s treatment.

The gene patents at the heart of the Supreme Court case, owned by Myriad Genetics MYGN, -3.83% , mandated a similar process when testing for the genetic markers of breast and ovarian cancer. Studies have found that the U.S. has granted more than 40,000 gene patents, and the American Civil Liberties Union estimates that 20% of human genes have been patented. But a recent analysis by Mason at Cornell, and Jeffrey Rosenfeld, assistant professor at the University of Medicine and Dentistry of New Jersey, found that as much as 41% of the human genome could be under patent.

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Myriad Genetics

When medical diagnostics and genetic research companies patent genes, they often end up squatting on swaths of DNA that have nothing to do with their treatments or products, scientists say. Besides breast cancer markers, Myriad’s patents also covered nearly 700 other genes, including markers for prostate, lung, and 17 other cancers, according to the Cornell analysis.

“They didn’t just own breast cancer; they owned all these other cancers,” says Rosenfeld. Before the Supreme Court ruling that Myriad could not patent those genes, there was no legal way to test for those diseases, he says: “It stopped people from doing research and from starting companies to develop new therapies.”

Along with Invivoscribe and Myriad’s leukemia and cancer genes, doctors say they will also have more ways to test for Canavan disease (a degenerative brain disease) and other illnesses that companies and organizations previously monopolized through patents. Scientists and doctors say they will also be free to pursue genetic research and develop DNA tests and treatments for diseases whose gene markers were previously protected by patents.

To be sure, companies with gene patents don’t always own exclusive rights to test for those DNA markers; while genes relating to Huntington’s disease, cystic fibrosis and colorectal cancer are patented, tests for those illnesses are more freely accessible, Mason says.

But doctors and other lab test companies like Quest Diagnostics will for the first time be able to perform Myriad’s breast and ovarian cancer risk test, which screens for the BRCA1 and BRCA2 genes. “We could do it tomorrow, we could give you the results tomorrow evening,” Mason says. Quest will begin offering those tests later this year, according to The Wall Street Journal.

Greater access to research and screening for genetic disease markers will likely lower the cost of those tests and eventual treatments, too. While Myriad charged $3,000 before insurance for its breast and ovarian cancer test, Rosenfeld expects the price to come down to $300 or $400, in line with other lab diagnostics, as more people can perform the screening: “I can sequence your whole genome today in the clinic for $5,000.”

So far, Myriad has not changed the price of its test, which the company says is more difficult to administer with meaningful results than would-be competitors might believe. “It is pretty unrealistic that a hospital or physician office would be able to perform this test given the complexity—much more likely in a large lab setting,” says spokesman Scott Gleason, adding that several labs have already announced their intentions to offer Myriad’s previously patented tests.

But medical researchers are more optimistic.”The floodgates are going to burst open with our ability to research genes, as well as what mutations give you greater or lesser risk for other genetic diseases,” Mason says.