Supreme Court blocks patenting of genomic DNA (Updated)
Opens the door for widespread testing of cancer genes.
The case grew out of patents held by Myriad Genetics, a company that has had a monopoly on testing for genetic defects in genes associated with breast and ovarian cancer. The genes in question, BRCA1 and BRCA2, were first isolated by scientists from the University of Utah who then patented their sequences. The university later transferred the patents to Myriad, which developed further patents to cover more detailed aspects of the testing process.
In its ruling, the Supreme Court notes that the sequences of these genes are naturally present in every human cell—and simply cutting them out of the genome and isolating them from the cell does not change that fact. As a result, no matter how much work and ingenuity it took to first identify the genes, the sequences remain natural products. Thus, they are not eligible for patenting.
The ruling does allow Myriad to retain some of its patents on the technical details of testing. Both of these genes are quite large, covering tens of thousands of bases of the genome. It's often more convenient to convert the mature RNA transcript to what's called a cDNA (complimentary DNA) and then sequence the much-shorter cDNA. This process, the Court ruled, is patentable, as it transforms the genes from their natural state. That means Myriad retains a monopoly on the fastest and cheapest way of identifying mutations. But due to the rapidly plunging costs of DNA sequencing technology, this advantage is relatively minor.
What follows is a more detailed look at the decision.
A return trip to the Supreme Court
Back in 2009, the ACLU led a collection of patients, researchers, and other interested groups in a suit that targeted Myriad's patents on the BRCA genes. The US Patent and Trademark Office has been granting patents on genes, including human genes, for years. The Myriad patents, however, provided a chance for a clear test of this. The company threatened to sue others for infringements of its patents, and a number of parties could viably claim they were harmed by Myriad's monopoly.The initial ruling seemed to bode poorly for gene patents. The ruling recognized that it wasn't anything about the specific form of the DNA involved in the testing that mattered. Instead, it is the DNA's information content, in terms of the protein it encoded, that was necessary to evaluate cancer risks. Since that information was a product of and interpreted by natural processes, it couldn't be subject to patent.
That ruling, however, was reversed in 2011. The Supreme Court later issued a key patent ruling and ordered the Appeals Court to reconsider Myriad in light of it. The case eventually made its way back to the Supreme Court, which heard arguments on it earlier this year.
Information is everything
Oddly, despite all the twists and turns, the Supreme Court ruling (written by Clarence Thomas) largely echoes the original ruling in the case, focusing on DNA's information content and not the specific chemical configuration of the DNA sequence that matters. Myriad argued that, in isolating DNA, they were making breaks between the BRCA genes and the surrounding chromosome, thus making a chemically distinct molecule. But Thomas, joined by the remainder of the court, rejected this idea.In a number of the patented genetic tests, "Myriad did not create or alter either the genetic information encoded in the BCRA1 and BCRA2 genes or the genetic structure of the DNA," the ruling states. Elsewhere Thomas notes, "The claims are not expressed in terms of chemical composition, nor do they rely on the chemical changes resulting from the isolation of a particular DNA section. Instead, they focus on the genetic information encoded in the BRCA1 and BRCA2 genes."
Defining things in terms of chemical composition wouldn't save the patents either. As the decision points out, if the patent was defined in terms of a specific DNA sequence, anyone could simply turn to the genome, look up a single nucleotide on either side, and then work with what's technically a different DNA molecule.
Again, the ruling leaves intact any claims about cDNA. When a human gene is first transcribed into RNA, it contains protein coding sections interspersed with non-coding regions. The non-coding sequences are then spliced out, leading to a mature RNA that's far more compact and mostly composed of protein-coding sequences. It's possible to convert this RNA back into DNA and then work with that. The resulting cDNA does not occur in nature (or, if it does, it does so rarely and as a result of a random accident). This all means that cDNAs can still be patented.
That leaves Myriad in control of the fastest and cheapest form of testing available. But, as noted above, working with genomic sequence is now relatively fast and cheap. The remaining patents aren't a significant barrier to anyone who wants to test for BRCA mutations. And a number of disease-causing mutations wouldn't be found using cDNAs anyway, since they affect non-coding regions that control the activity or splicing of the gene.
(More generally, it's worth noting that the patents on distinct combinations of genes found in things like genetically modified crops and gene therapy constructs remain valid.)
Innovation and basic biology
A few things about the specific language of the decision seem noteworthy. First, the Supreme Court is getting worried that excessive patenting is becoming stifling. The new decision quotes a past one (Mayo vs. Prometheus) in saying that scientific tools like abstract ideas and laws of nature are exempt from patenting. "Without this exception, there would be considerable danger that the grant of patents would 'tie up' the use of such tools and thereby 'inhibit future innovation premised upon them.'" Although the Mayo decision is clearly relevant to this case, there was no obvious reason to note the danger of patents inhibiting further innovation here. The wording suggests that Thomas referenced it to make a point.The other interesting issue comes from Scalia's separate concurrence. He completely agrees with the decision itself, but he is unwilling to sign on to any of the technical descriptions of the biology. In his one-paragraph concurrence, Scalia writes that he cannot understand them and cannot even understand whether the expert descriptions of them are accurate. (Which is somewhat ironic, given that Scalia once accepted that "creation science" was scientific based solely on a few creation scientists saying it was.) All he knows is that isolated DNA is identical to a portion of DNA in its natural state. That's enough for him to concur with the decision.
To an extent, Scalia was right not to sign on. The opening paragraph of the decision contains two errors in its description of DNA (the bonds between the DNA strands are hydrogen, not chemical as it claims, and not all non-coding DNA is part of an intron). These don't affect the decision in any way, but they do suggest that the Supremes are having a bit of trouble with biology.
Given how important issues of genetics and genomics are becoming in terms of privacy, health, and the economy, it might behoove the court to consider a refresher course. I'd imagine that the National Academies of Science and the American Association for the Advancement of science, both based in Washington, would be happy to help.
No comments:
Post a Comment