In a Supreme Court test of whether a company can be granted a patent on the genes in the human body, a majority of the justices indicated during Monday's oral arguments that the court is likely to rule that a human gene can’t be patented.

It would be one thing, several of the justices said during Monday’s oral arguments, for a company to seek a patent on a test for breast cancer that was developed by analyzing a human gene, but it would be going too far to be awarded a patent on the gene itself.

"What's the difference between snipping off a piece of the liver or kidney, and seeking a patent on that, and seeking a patent on a piece of a gene?" asked Justice Sonia Sotomayor.

Justice Samuel Alito made a different analogy, to someone seeking a patent on a plant found in the Amazon rain forest that bore leaves containing a cancer cure. "You could patent the process used to get the chemical out and the use of the result, but you cannot patent the plant," he said.

Stelios Varias / Reuters file photo The U.S. Supreme Court in Washington

The case, Association for Molecular Pathology v. Myriad Genetics, involves a test that has helped guide more than a million women in their medical decisions. The test can determine whether the composition of their genes makes them more likely to get breast or ovarian cancer.

Myriad Genetics, a Utah company, owns patents on two parts of human genes known as BRCA 1 and BRCA 2, named for the first two letters of the words breast and cancer.

Women with mutations in those genes face up to an 85 percent risk of getting breast cancer and up to a 50 percent risk of ovarian cancer. Because of the patents, Myriad has a monopoly on performing all diagnostic tests related to BRCA 1 and BRCA 2.

In the past three decades, the federal government has granted nearly 3,000 similar patents on genetic material. Without such protection, Myriad argues, companies would be less willing to spend the money required for making genetic discoveries.

"Countless companies and investors have risked billions of dollars to research and develop advances under this promise of stable patent protection," according to Gregory Castanias, a Washington, D.C, lawyer who argued the case for Myriad.

The idea of patenting DNA material has provoked a strong debate among scientists, and many have lined up on opposite sides of the case.

"Human genes should not be patented," says James Watson, the Nobel Prize winner and co-discoverer of the double helix structure of DNA.

"Life's instructions ought not be controlled by legal monopolies created at the whim of Congress or the courts," he says.

But a group of researchers at the University of Maryland is among those arguing just the opposite. "The costs are outweighed by the benefits stemming from the fruits of increased inventive activity," they say in their friend-of-court brief.

In the 220 years since Thomas Jefferson wrote the cornerstone of U.S. patent law, the courts have agreed on a general principle: patents protect inventions, not products of nature. A central issue in this case is whether Myriad has obtained a patent on something already in the body or has created something new.

The ACLU, representing a group of scientists, doctors, and cancer patients, claims that Myriad has merely removed from the body something that was already there -- the DNA sequence making up the BRAC 1 and BRAC 2 genes. Because it is a creation of nature, the ACLU says, it cannot be protected by a patent, even though Myriad claims that removing it is what makes it useful.

"Gold does not become patentable once taken out of a stream because it can be used in jewelry. Kidneys do not become patentable once taken out of a body because they can be transplanted," says the ACLU's Christopher Hansen.

Myriad's exclusive patent, says the ACLU, creates a monopoly that denies women the ability to seek a second opinion, based on another test of the genetic material, and dissuades other laboratories from pursuing research on the patented genes.

The ACLU also contends that because the test costs roughly $3,000, many women cannot afford it or lack the necessary insurance coverage. If the gene was not under patent protection, the ACLU says, competition would make the test cheaper.

But Myriad argues that removing the gene sequence from the body requires breaking chemical bonds that lock it into place, thereby creating a new chemical entity.

The resulting genetic materials, the company says, "were never available to the world until Myriad's scientists applied their inventive faculties to a previously undistinguished mass of genetic matter."

Myriad cites a line of cases finding patent eligibility for naturally occurring substances that were isolated and purified, including aspirin, vitamin B12, and adrenaline derived from cows.

As for availability, the company says the cost of the test is covered by private insurance, Medicare, and Medicaid. It also says many other labs provide second opinions regarding the company's test results and that thousands of researchers have done studies on the gene sequence involved, unimpeded by the patent.

The Obama administration has urged the court to be deeply skeptical of Myriad's broad claim of what can be patented. The Justice Department's brief in the case says the public interest has consistently been given precedence by the Supreme Court "in avoiding undue restrictions imposed by patents that effectively preempt natural laws and substances."

NBC's Tom Curry contributed to this report.

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