Companies cannot patent individuals' genes, the Supreme Court said in a unanimous ruling Thursday.
The case involved two genes that help detect women's risk of developing breast cancer. A private company, Myriad Genetics, had patented the genes, known as BRCA1 and BRCA2, saying it had invented a new diagnostic tool by isolating those genes.
Privacy advocates balked, however, and said a private company should not be able to patent naturally occurring parts of the human body. Myriad did not modify the genes to detect breast cancer risk — it simply removed them from the body.
The court sided against Myriad on Thursday, ruling that a naturally occurring strand of DNA cannot be patented because it is a "product of nature."
But synthetic DNA can be patented, the court said.
The gene-patenting case received particular attention because the BRCA1 and BRCA2 tests are becoming increasingly common. (Actress Angelina Jolie recently underwent a double mastectomy after the same test showed that she was at a high risk for developing breast cancer.)
Privacy advocates, including the American Civil Liberties Union, had argued before the court that Myriad's patents went so far as to prohibit female scientists from evaluating their own genes.