In Big Win For Biotech Industry, Isolated DNA Remains Eligible For Patenting

Isabelle Blundell, Ph.D.
Nancy C. Wilker, Ph.D., J.D.

By Isabelle Blundell, Ph.D and Nancy Wilker, Ph.D. Members of the Life Sciences Practices Group

October 2012 IP Update

In the latest installment of that gene-patenting saga known as the Myriad case, the Court of Appeals for the Federal Circuit reaffirmed its earlier holding that isolated DNA, including cDNA, is eligible subject matter under section 101 of the Patent Act.

The August 16 decision in Assoc. for Molecular Pathology v. U.S. Patent and Trademark Office, as the Myriad case is formally known, is a good occasion to consider how this and related holdings affect not just the biotech industry, but the pharmaceutical and other industries providing diagnostic-testing services.

The Myriad case came to prominence in March 2010, with the startling decision of Judge Robert Sweet of the federal district court in Manhattan. Judge Sweet held that isolated DNA is directed to a product of nature and is therefore not patentable subject matter. Methods for using the isolated DNA were likewise directed to non-patentable subject matter, he ruled. As we discussed at the time, the decision rocked the biotech industry.

In July 2011, much to the relief of the industry, a three-judge panel (Lourie, Moore, and Bryson) of the Federal Circuit overturned part of Judge Sweet’s decision, concluding that isolated DNA molecules are indeed patentable subject matter. However, as we reported, the appellate panel did agree with the lower decision that the method-of-testing claims were largely unpatentable, but held that one method claim, drawn to a method for screening potential therapeutics using a transformed cell, was patent-eligible subject matter.

Not surprisingly, given the stakes, the plaintiffs requested Supreme Court review, causing fresh anxiety in the biotech world. The high court, however, declined to review the case so soon after delivering its ground-breaking decision on diagnostic methods in Mayo Collaborative Services v. Prometheus Laboratories, Inc. (see our discussion or Prometheus here). Instead, it sent Myriad back to the Federal Circuit for reconsideration in light of Prometheus.

The same panel of Federal Circuit judges reconsidered the case and, in the same 2-to-1 split, stood by its previous holding that isolated DNA claims and methods for screening potential therapeutics using a transformed cell were patentable, but that methods for detecting or screening for the isolated DNA by “analyzing” or “comparing” sequences were not patentable.

In a unanimous portion of its decision, the Federal Circuit panel held that, with regard to the isolated DNA, Prometheus — which laid down principles for determining whether inventions are too closely tied to laws of nature to be patent eligible — was simply not a controlling precedent.

In reaching its decision as to the patent eligibility of isolated DNA claims, the Federal Circuit panel relied not on Prometheus, which was directed to diagnostic methods, but instead on earlier Supreme Court decisions, Chakrabarty (1979) andFunk Brothers (1948), which were directed to compositions of matter: man-made living organisms (genetically engineered bacteria) and mixtures of known, naturally-occurring bacteria, respectively.

cDNA was unanimously held to be eligible subject matter, because it lacks those portions of the gene that do not encode for amino acids. This factor represents a profound change in the nucleotide sequences relative to natural DNA in the chromosome.

However, the question of the eligibility of isolated DNA that is not cDNA spurred a dissent from Judge Bryson. The dueling opinions agreed that isolated DNA was structurally modified from its original form in the chromosomes. Since the claimed isolated DNA was cleaved from the chromosome, it necessarily had distinct chemical bonds, was free of the histone proteins, and was separated from contamination from its original environment.

In the majority opinion, the isolated DNA was found to be different from natural DNA in its name, its character and its use. The judges in the majority emphasized that covalent bonds define the boundaries between one molecule and another and thus, for compositions of matter, the presence of distinct covalent bonds points to patent eligibility, particularly when those distinguishing bonds are man-made.

The dissenting judge, however, betraying a scant understanding of chemistry and of the teachings of Linus Pauling, gave little weight to differences in the covalent bonds of the isolated and the natural DNA, saying that the changes are incidental to the extraction process and possess “no magic.”

The majority opinion rejected the plaintiffs’ argument that the informational content of the isolated DNA is the same as that found in the natural DNA: It held that the content which relates to the function of the DNA is irrelevant, considering that there are clear structural distinctions between isolated and natural DNA.

The dissenting opinion gave little weight to these distinctions, instead stressing that the function of the isolated DNA is unchanged from that of the natural DNA, because they have the same sequence, code for the same proteins and represent the same unit of heredity. This view appears to overlook that isolated DNA in fact possesses additional utility not available from the natural DNA, that is, it can be used to identify a gene mutation in a sample or, when sequenced, the structural identity of the gene.

The dissenter also registered concern over the breadth of coverage of the claimed isolated DNA in that it included many variations that Myriad had not discovered and could not have described. However, breadth and description have never been factors for eligibility under section 101, and are more germane to the enablement and written description requirements of section 112.

The majority admonished the lower court for yielding to policy concerns, Citing the Supreme Court’s advice in Bilski that courts “should not read into the patent laws limitations and conditions which the legislature had not expressed,” the Federal Circuit observed that the judicial system is not best situated to create categorical exclusions of eligible subject matter. Rather, elected representatives in Congress are in the best position to decide on such exclusions, something they chose not to do while legislating comprehensive patent reform (the America Invents Act) during the pendency of this case.

Two remaining issues found the entire panel in agreement. As in its 2011 decision, and now with the guidance from Prometheus, the Federal Circuit predictably found that the method claims requiring only the mental steps of “analyzing” or “comparing” were unpatentable.

Surprisingly, though, the court stood by its earlier view of the patent eligibility of the method claims for screening cancer therapeutics using a transformed cell, notwithstanding Prometheus. The court reasoned that “transformed eukaryotic host cells” points to cells “derived by altering a cell to include a foreign gene [which resulted] in a man-made, transformed cell with enhanced function and utility.” In this way, the court was able to hold that such claims were patent eligible.

On September 25, 2012, the ACLU once again asked the Supreme Court to review the case, hopeful that it would side with the dissenting opinion, despite the latter’s poor understanding of the nature of chemistry. The chemical bond, including the covalent bond, is the fundamental principle of modern chemistry and distinguishes the claimed isolated DNA from natural DNA and, indeed, distinguishes us from the primordial soup.

If the Supreme Court is mindful of this distinction, it will likely affirm the patent eligibility of isolated DNA, if it opts to review the Myriad Genetics case at all.