By Julie Nixon
Last Thursday, the Supreme Court delivered its judgment in the Myriad case. The nine Justices held that “a naturally occurring DNA segment is a product of nature and not patent eligible merely because it has been isolated, but cDNA is patent eligible because it is not naturally occurring”. This judgement means that other companies may now offer tests using the BRCA genes, the genes that had been patented by Myriad, hopefully resulting in cheaper testing for breast and ovarian cancer susceptibility. But to say the decision means that genes cannot be patented is far from correct-only naturally occurring human genes cannot be patented.
To explain I must elaborate on what “cDNA” actually is. In its natural form, and at a very basic level, genomic DNA consists of coding and non-coding parts. The coding regions are “translated” into proteins in human cells. Before this happens the non-coding regions are “spliced” out of an intermediate molecule called messenger RNA (mRNA) that has been “transcribed” (copied to put it simply) from the genomic DNA. Scientists can isolate the mRNA, which is much more unstable than DNA, and then perform a very easy enzymatic reaction to create “complimentary DNA” (cDNA) which differs slightly in composition to the mRNA found in nature, but has the same genetic information as a gene. So yes, cDNA technically is a man-made product, but it is the compliment of that found in nature. And to generate it in a lab does not require much effort.
The Supreme Court has found a way of actually allowing genes to be patented by holding cDNA to be patent eligible. My opinion is that cDNA is not markedly different to that found in nature and there is nothing ground breaking or innovative in creating it in a lab environment.
However I can acknowledge that the decision creates a balance between researchers and businesses. Human genes in their natural form can now be used to further medical research without researchers fearing infringement, and biotech companies can still patent informative parts of a gene and so incentivise investment.
I am also delighted the judges rejected the Myriad argument that genomic DNA could be patented because isolated DNA has a different physical structure and chemistry than genes within the body. Whether in vivo or in vitro, genomic DNA carries the same information. However cDNA has a different chemical structure to mRNA but carries the same genetic information, and creating cDNA is not a huge act of invention, yet the Supreme Court accepts cDNA can be patented.
Whatever the reasoning behind the decision, both sides in the case are claiming victory. What remains to be seen are the practical implications of the ruling. Important genetic information is still patent eligible so we may still see in the future ramifications for personalised medicine.