(WASHINGTON) -- The Supreme Court ruled on Thursday that isolated human genes cannot be patented, a partial defeat for Myriad Genetics, a company that had been awarded patents on the so-called BRCA1 and BRCA2 genes in the 1990s.
But the court said DNA molecules engineered by man -- including so-called "cDNAs" -- are eligible for patents.
"Myriad did not create anything," Justice Clarence Thomas wrote for a unanimous court. "To be sure, it found an important and useful gene, but separating that gene from its surrounding genetic material is not an act of invention."
Synthetic "cDNA" does not present the same obstacles to patentability as naturally occurring isolated DNA segments, Thomas wrote.
The court on Thursday adopted a middle-ground position that the U.S. government had put forward.
"Today, the court struck down a major barrier to patient care and medical innovation," said Sandra Park, senior staff attorney with Women's Rights Project of the American Civil Liberties Union, which had challenged the patents.
"Myriad did not invent the BRCA genes and should not control them. Because of this ruling, patients will have greater access to genetic testing and scientists can engage in research on these genes without fear of being sued," she said.
Biotechnology companies, racing to create personalized tests and treatments tailored to a person's genetic makeup, were closely watching this case.
Myriad has not yet reacted to the decision.
Professor Lori Andrews of the Illinois Institute of Technology Chicago-Kent College of Law said, "Today's decision allows any doctor or scientist to use the breast cancer gene for diagnosis or treatment. This means all genetic tests will become affordable and more researchers will be able to look for cures."
Andrews filed a brief opposing Myriad's patent but says that biotechnology companies will be adequately protected if they genetically engineer a product.
The challenge to Myriad's patents was brought by scientists, researchers and patients who believed that the patents stood in the way of further research on the genes and limited the availability testing. The ACLU represented the groups in court and argued the court should invalidate the patents because they cover a product of nature and not an actual invention.
Because of the patents, Myriad was the only place in the United States to go for diagnostic testing at a $3,340 price tag.
Myriad's lawyers had fiercely defended the company's patents, arguing that they have been essential to the development of diagnostic tools to help patients and doctors assess the risks of cancer.
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