Association for Molecular Pathology v. Myriad Ruling: What is Synthetic DNA?

In a unanimous decision released Thursday, the Supreme Court ruled that while synthetic DNA is patentable, naturally isolated DNA is not. The ruling, based on Myriad Genetic's claim to the BRCA1 and BRCA2 genes — both of which are key indicators of breast and ovarian cancer risk — was decided in large part because of the distinction that synthetic DNA is not naturally occurring. But what exactly is synthetic DNA?

Synthetic genes are genes produced in a laboratory by artificial gene synthesis. These genes are not based on any naturally pre-existing DNA sequences, and the possibilities for unique synthetic genes is almost endless. These genes are particularly useful for vaccine development, gene therapy, and molecular engineering.

On the other hand, the now non-patentable DNA consists of genes that are isolated from the natural world, "captured," and then copied. Myriad argued that it was not patenting anyone's genes, but rather the lab-made copies. However, because the copies are identical, patenting their gene sequence would in effect patent the genes present in all of us.

Prior to the case, the U.S. Patent Office accepted patents on isolated DNA sequences as a composition of matter, but today's decision stated that because isolated DNA is captured, it is not invented but rather naturally occurring, and thus is not patentable; the same way no one can patent sugar, coal, or water. According to the ACLU, 20%t of all identified human genes have been patented.

During oral arguments, Gregory Castanias, Myriad's lawyer, suggested an analogy to baseball: "A baseball bat doesn’t exist until it's isolated from a tree," he said. "But that’s still the product of human invention to decide where to begin the bat and where to end the bat."