The United States Supreme Court recently ruled that genes or other naturally-occurring pieces of DNA are patent ineligible subject matter in Association for Molecular Pathology, et al. v. Myriad Genetics, Inc., et al. No. 12-398, slip op. (U.S. June 13, 2013), hereinafter Myriad. (View opinion here).

The Court in Myriad stated: "We hold that a naturally occurring DNA segment is a product of nature and not patent eligible merely because it has been isolated, but that cDNA is patent eligible because it is not naturally occurring." Slip op. at 1. Complementary DNA (cDNA) contains the same protein-coding information found in a segment of natural DNA but omits portions within the DNA segment that do not code for proteins. Sequences of DNA nucleotides contain the information necessary to create strings of amino acids, which appear in proteins. Only some DNA nucleotides code for amino acids. These nucleotides are known as “exons.” Nucleotides that do not code for amino acids, in contrast, are known as “introns.”  cDNA is thus an "exons-only" molecule. Slip. op. at 2, 3, 16.

According to the Court, cDNA does not present the same obstacles to patentability as naturally occurring, isolated DNA segments, since its creation results in an exons-only molecule, which is not naturally occurring and when introns are removed, something new is "unquestionably" created. Id. at 16–17. On this basis, the Court concludes that cDNA is not a “product of nature,” and therefore patent eligible under 35 U.S.C § 101, which provides that:

Whoever invents or discovers any new and useful . . . composition of matter, or any new and useful improvement thereof, may obtain a patent therefor, subject to the conditions and requirements of this title. 

Id. at 17, 10. 

Comments on the decision have ranged from calling it a victory to a disaster, and everything in between, often forecasting dire consequences both for proponents and opponents of so-called "gene patents." In order to better assess future strategies, however, it is important to apply the holding to the patent claims at issue, such as claims 1, 2, 5, and 6 of U.S. Patent No. 5,747,282 ("the '282 patent"), identified as representative of the claims at issue in Myriad. 

Claim 1 of the '282 patent claims "an isolated DNA coding for a BRCA1 polypeptide, said polypeptide having the amino acid sequence set forth in SEQ ID NO:2."

Since this claim is directed to a naturally occurring DNA sequence, it is invalid under Myriad. At least this much seems clear, since the Court explained that "Myriad’s claims are not saved by the fact that isolating DNA from the human genome severs the chemical bonds that bind gene molecules together." Slip op. at 1; 14. 

Claim 5 of the '282 patent is a dependent claim that claims "an isolated DNA having at least 15 nucleotides of the DNA of claim 1." This claim also encompasses isolated naturally occurring DNA, and is therefore similarly invalid in view of Myriad. 

Claim 2 of the '282 patent is a dependent claim that claims "the isolated DNA of claim 1, wherein said DNA has the nucleotide sequence set forth in SEQ ID NO:1."

SEQ ID NO:1 is a cDNA molecule as noted by the Court. Claim 2 recites an isolated full-length cDNA sequence, which, according to Myriad, is non-naturally occurring and therefore patentable. Claim 2 appears to be a valid claim.

Moving on to claim 6 of the '282 patent, this is a dependent claim that claims "an isolated DNA having at least 15 nucleotides of the DNA of claim 2." This claim encompasses isolated fragments of non-naturally occurring cDNA, which appear to be patentable; however, claim 6 is written broadly enough to also encompass isolated fragments of naturally occurring DNA. As the Court noted, "very short series of DNA may have no intervening introns to remove when creating cDNA... [A] short strand of cDNA may be indistinguishable from natural DNA." Slip op. at 17. Claim 6, therefore, arguably may be invalid in view of Myriad, since a fragment of an "unquestionably" synthetic molecule may not be distinguishable from naturally occurring DNA.

As claim 6 of the '282 patent demonstrates, what may have initially appeared to be a straightforward distinction between the "synthetic" and the "natural" is anything but. Considering that the test for patent-eligibility has been considered by the Court to be a "threshhold" test," having such a gray area as to cDNA fragments may pose a challenge to patent practitioners drafting claims which are both broad enough to protect an invention, yet distinguishable from naturally occurring DNA.

The Court itself offered little guidance on how to apply the distinction. According to the Court, "Myriad’s claims are simply not expressed in terms of chemical composition, nor do they rely in any way on the chemical changes that result from the isolation of a particular section of DNA. Instead, the claims understandably focus on the genetic information encoded in the BRCA1 and BRCA2 genes." Id. at 14. Myriad's "claim is concerned primarily with the information contained in the genetic sequence, not with the specific chemical composition of a particular molecule." Id. at 15 (emphasis in original). The opinion concludes: "[w]e merely hold that genes and the information they encode are not patent eligible under §101 simply because they have been isolated from the surrounding genetic material." Id. at 18 (emphasis added). Assessing the informational content of DNA-related claims will likely blur the line which the Court has tried to draw because even the Court's own description of cDNA recognized that it contains "the same protein-coding information found in a segment of natural DNA." Slip op. at 1 (emphasis added).

In addition, the Court specifically expressed no opinion on yet another potentially inventive aspect of DNA, namely, "the patentability of DNA in which the order of the naturally occurring nucleotides has been altered." Slip op. at 18.

In view of the above, U.S. Patent applicants wishing to obtain claims to DNA and other nucleic acids should take care not to define the DNA solely in terms of its information content, and likewise adopt other strategies to show that the claimed subject matter is "synthetic," such as in a recombinant form, and is not-naturally occurring. One such strategy gleaned from the opinion would involve expressing the molecule more in terms of chemical composition and describing the chemical differences between the isolated molecule as compared to its natural counterpart.

Given that this ruling, which related to DNA, will likely be applied to other (macro)molecules which are naturally-occurring in any organism, similar strategies will apply for patentees wishing to obtain claims to proteins, carbohydrates or lipids, for example. The informational content aspect of the court's reasoning may not be of any relevance for these molecules, however, since they do not encode information in the same way as DNA. 

The success of any of these strategies is speculative, at best. As many commenters have noted, the full implications of Myriad case will likely take years to resolve.