From the 1980s, scientists from around the world started to search for specific genes that were associated with increased hereditary risk for breast cancer.  By 1990, two genes, BRCA1 and BRCA2, were discovered that if they had specific mutations/alleles would impart an increased risk for breast cancer in women.

In 1994, Myriad Genetics announced that they had sequenced the mutant alleles of BRCA1 and in the subsequent year, they sequenced the mutant alleles for BRCA2.  Right away, Myriad sought and obtained two different kinds of composition patents covering the genetic material of the BRCA genes.  First, they patented the isolated DNA molecules of BRCA1 and BRCA2.  Second, they obtained patents to “complementary DNA” (cDNA) associated with each of the BRCA genes.  cDNA contains only the coding sequences of the gene.  Unlike DNA, it normally does not exist in the body.

With these composition patents, Myriad started to offer exclusive screening of the BRCA genes to women wanting to know their hereditary cancer risk.  However, in 1996, the Genetic Diagnostic Laboratory (“GDL”) at the University of Pennsylvania also started to offer diagnostic screening for the BRCA genes.  Myriad then sent a series of cease-and-desist letters notifying GDL to stop offering BRCA screening to which GDL complied.  At around the same time, Myriad filed several patent infringement suits against other parties that were offering BRCA testing.  The suits were dismissed when these other parties ended their BRCA testing.

A few years later, numerous parties, including doctors at GDL, initiated legal action in the Southern District of New York seeking a declaratory judgment that Myriad’s BRCA patents were invalid.  The District Court granted summary judgment in favor of the plaintiffs, declaring that Myriad’s composition claims for both isolated DNA and cDNA were not patentable under the “products of nature” exception.  In making the ruling, the District Court relied on the decision by the U.S. Supreme Court in Chakrabarty, 447 U.S. 303 (1980) that required a patentable composition of matter to include “markedly different characteristics” from a product of nature.  Thus, the District Court was unconvinced that simply isolating a DNA molecule would make it “markedly different” in a legally significant manner.  Further, the District Court considered the coding sequences of cDNA to be identical to portions of naturally occurring DNA, and accordingly, the District Court deemed the cDNA was also not patentable under the “products of nature” exception.

Myriad then appealed to the Court of Appeals for the Federal Circuit.  In its decision, the Federal Circuit reversed holding that both isolated DNA and cDNA to be patentable.  In making the decision, the Federal Circuit focused on whether the claimed DNA molecules exist in a “distinct chemical form” from DNA in the human body.

Afterwards, the U.S. Supreme Court granted certiorari, but the Supreme Court vacated the judgment and remanded for reconsideration in light of its Prometheus decision.

When the case returned to the Federal Circuit on remand, a three-judge panel reaffirmed its earlier decision that both isolated DNA and cDNA are patentable.  In regards to the isolated DNA, one judge ruled that the “distinct chemical structure” of isolated DNA, which is achieved by “cleaving” the chemical bonds of naturally occurring DNA molecule made it patentable.  Another judge rested her decision on the US Patent & Trademark Office’s longstanding practice of granting patents for isolated DNA – unwilling to disrupt the “settled expectations of the biotechnology industry” by reversing the longstanding practice.  Only one judge dissented to the patentability of isolated DNA contending that the cleaving of the DNA only effected “incidental” changes in the naturally occurring molecule.  As for the cDNA, all three judges agreed that it was patentable having a form and utility distinguishable from naturally occurring DNA.   

The U.S. Supreme Court granted certiorari and partially reversed.  The Supreme Court concurred with the Federal Circuit’s decision that cDNA was patentable, but it held that isolated DNA to be unpatentable under the products of nature exception.

The Supreme Court made its decision with Chakrabarty central to its inquiry.  Following Chakrabarty, the Supreme Court rejected all the rationales of the Federal Circuit for the patentability of isolated DNA.  First, it addressed the argument that cleaving of chemical bonds renders the isolated DNA a distinct composition of matter.  The Supreme Court noted that Myriad’s patent claims focused on genetic information as opposed to chemical composition, and therefore, the Supreme Court observed that  the genetic information of an isolated BRCA gene is identical to the information possessed in the in the naturally occurring DNA.  Next, the Supreme Court considered the argument that deference should be shown to the US Patent & Trademark Office’s longstanding practice of granting patents to isolated DNA.  However, this argument was weakened by the amicus curiae offered by the United States that argued against the patentability of isolated DNA.

As for the patentability of the cDNA, the Supreme Court affirmed the decision by the Federal Circuit being satisfied the cDNA was not naturally occurring.  The Supreme Court further noted that cDNA was unquestionably something created by lab technicians, and thus, cDNA fell outside the products of nature exception.

In conclusion, the Supreme Court considered that DNA is essentially information.  Myriad’s patent claim regards DNA as information, and accordingly, the Court treats it as information.  The minor chemical differences between naturally occurring DNA and isolated DNA do not change the informational aspect of DNA relative to its naturally occurring state, and thus, isolated DNA is not patentable.  However, the creation of cDNA in the laboratory does affect this informational component by removing the non-expressing portion of the DNA sequence, thus producing a non-naturally occurring DNA sequence.  This change in the informational content is sufficient to render cDNA sequence patentable.