In a decision that issued on 5 July 2016 (“Cargill Incorporated v Dow AgroSciences LLC [2016] APO 43”), the Australian Patent Office confirmed that a nucleic acid that has been codon-optimised (i.e. where one or more nucleotide triplets known as “codons” have been altered) defines patentable subject matter even if it codes for the same naturally-occurring protein as its naturally-occurring nucleic acid counterpart.
Here, I provide a brief summary of the Office’s views on the patentability of codon-optimised nucleic acids following the High Court’s Myriad decision (D’Arcy v Myriad Genetics Inc [2015] HCA 35) that issued late last year.
Manner of manufacture, nucleic acids and codon-optimisation
Claim 31 of the applicant (Dow)’s application recites “A polynucleotide comprising a sequence of nucleotides shown in SEQ ID NO: 1”.
Interestingly, although the opponent (Cargill) did not oppose claim 31 under the manner of manufacture (patentable subject matter) ground, the Delegate invited both parties to provide submissions on claim 31 in light of the recent findings in Myriad with respect to claims to nucleic acids.
For a bit of background, at [41], the Delegate briefly summarised Myriad as follows:
“In Myriad at [37], the High Court made it clear that it was not concerned with “gene patenting” generally but only with three claims encompassing isolated nucleic acids coding for a mutant or polymorphic BRCA1 polypeptide where the claimed class of nucleic acids was broadly defined in terms of it containing one or more of a large number of specified mutations or polymorphisms (sequence variations) in comparison to the coding sequence for the BRCA1 polypeptide represented by SEQ ID NO: 1. The majority found at [89]-[92] that although the claims were formulated as product claims, the substance of the claims to nucleic acids was the genetic information embodied in, and conveyed by, the nucleic acid sequence. The High Court found that the genetic information was naturally-occurring and had not been “made” by human action and, as a consequence, the claims did not define a manner of manufacture (at [91], [95]).”
Only Dow provided submissions and, to make it clear that the substance of claim 31 was “made” by human action, Dow submitted that the claimed nucleic acid sequence codes for a delta-9 desaturase gene derived from the fungus A. nidulans, which has been codon-optimised for efficient expression of the protein in plants. Dow further submitted that “the codon-optimisation is an important man-made variation to the naturally occurring sequence, notwithstanding that the coding regions may code for the same (naturally-occurring) protein” (as they did in the present case).
Given that the nucleic acid of claim 31 had been codon-optimised (even though it encoded the same naturally occurring protein as its naturally occurring nucleic acid counterpart), the Delegate found that the genetic information had been modified unlike the situation in Myriad (where both the naturally-occurring nucleic acid and its corresponding cDNA sequence were found to be directed to unpatentable subject matter).
The Delegate also found that the economic utility of the claimed polynucleotide in altering (reducing) the levels of saturated fats in canola plants, seeds and oils was clear and was therefore satisfied that claim 31 defined an invention that is a manner of manufacture.
Conclusion
Thus, while isolated naturally occurring nucleic acids and cDNA (which is synthesised in the laboratory but replicates a naturally occurring sequence of genetic information in the form of exons) remain unpatentable in Australia, nucleic acids that have been codon-optimised (e.g. to optimise protein expression/production in a particular environment), and have economic utility, are considered patentable subject matter.
This may encourage some patent applicants to codon-optimise naturally occurring nucleic acids of interest in an attempt to overcome the more stringent manner of manufacture (patentable subject matter) requirements introduced for genes/nucleic acids and cDNA in Australia following Myriad.