Myriad is asking U.S. District Court Judge Robert Shelby to issue an injunction requiring the companies to immediately halt their testing programs because they infringe on parts of Myriad's patents not invalidated by the June ruling from the Supreme Court.
But the two competitors argue that Myriad's tests rely on genetic material that is not eligible to be patented under that decision and that their tests are based on new knowledge, methods and technologies not available when Myriad received its patents nearly 20 years ago.
David Mangum of Salt Lake City, the lead attorney for Myriad, said Ambry and Gene by Gene tests were dependent on a synthetic genetic material called a primer on which Myriad still holds patents. Under the Supreme Court decision, Myriad's primers are eligible for patents because they are not performing natural functions, he said.
"They perform an entirely different function … that does not occur in nature," Mangum said.
But William G. Gaede III, a California attorney who represents Ambry and Gene by Gene, said Myriad's primers contained a sequence of natural genetic material, making them ineligible to receive patent protection under the Supreme Court decision that said DNA isolated from the body is still a natural substance and cannot be patented.
"It didn't mean you take a product of nature out of a product of nature and make it patent eligible," he said.
He also argued that Ambry's tests take in the whole human genome and not just the segment where the BRCA1 and BRCA2 genes occur. Myriad's test, on the other hand, looks only at those sequences and uses discoveries made long before the entire human genome was published, Gaede said.
"They could not compare the whole genetic sequence because the whole sequence didn't exist when the patent was filed," he said.
But Mangum argued that court cases have recognized that pieces of natural objects used as part of something that is different and inventive can receive patents. He pointed to the Supreme Court's Myriad decision where the justices said cDNA, actual DNA that has been changed or manipulated in the laboratory so it is not in its natural state, can be patented.
That means Myriad's primer using a DNA sequence for a purpose other than what it did in nature is eligible for a patent, Mangum said.
The case is in some ways a replay of portions of the one that went before the Supreme Court. In that case, Myriad was sued by the American Civil Liberties Union and Public Patent Foundation on behalf of patients, researchers, medical groups and women's health advocates who argued Myriad couldn't patent the genes related to breast and ovarian cancer because they are products of nature.
Gaede tried to push some of the same emotional buttons of that case when he mentioned how women's BRCA1 and BRCA2 genes are what Myriad wants to control.
"They lay claim to the gene itself," he said.
The hearing could last through Thursday. Shelby said no decision would be forthcoming until the sides have a chance to file additional materials and then make final arguments in a second hearing.