The earliest genetic patents were issued in 1982, following the U.S. Supreme Court case of Diamond vs. Chakrabarty, which opened the door to patenting biotechnology discoveries. Since then, the core of the debate over gene patents has been whether or not the discovery of a gene or sequence of DNA rises to the level of invention required by Title 35 of the United States Code, which lays out the criteria that must be satisfied for a patent to be granted. According to the Code, a patent may only be granted on "any new and useful process, machine, manufacture, or composition of matter, or any new and useful improvement thereof." Laws of nature, natural phenomena, and abstract ideas cannot be patented. Even if this first hurdle is passed, the invention must be novel; the existence of 'prior art' shows that someone else invented it first, of course. Also, the invention cannot be obvious to "a person having ordinary skill in the art to which said subject matter pertains."



In the case of gene patents, critics have pointed out that such patents fail to meet most or all of these criteria. Firstly, genes are naturally occurring, and while much intellectual effort may have gone into discovering them within the DNA sequence, discovery is not the same as invention. Secondly, with the completion of the Human Genome Project in 2003 all of the human gene sequences were in the public domain and, therefore, prior art. Finally, many argued that discovering the location of a gene never rose above the bar for being non-obvious; certainly by the late 1990s the practice was common place. Despite the criticism, DNA patenting has proven to be a very active area. Although it is difficult to determine a precise number, some estimates assert that a fifth of the human genome is subject to patent claims.



Patents are issued to encourage innovation, and provide protection to allow those investing in an innovation the opportunity to maximize the profit from their investment. Patents issued for genetic technologies such as new methods of DNA sequencing are no different and their issuance has been extremely valuable to those developing products based on genetic discoveries. However, when patents limit the use of basic genetic information, they threaten to inhibit or unduly constrain biomedical research, and the translation of research discoveries to clinical applications.



Indeed, one of the early principles agreed upon by leaders of the Human Genome Project was that the DNA sequence generated should be freely available to the public. This principle was codified in the 1997 Bermuda Principles, which set forth the expectation that all DNA sequence information should be released into publicly available databases within 24 hours of being generated. This policy of open access to the genome has been a core ethos of genomics ever since.



Over the years that this debate has occurred, there have been concerns that large numbers of patents associated with the human genome would limit the integration of genomic medicine into health care because of either restrictive patents or prohibitive costs. Diagnostic tests on patented genes cannot be invented around, as is possible with other patents. This is because the actual DNA sequence to be tested is claimed in the patent, not the method of analyzing the gene to determine its sequence, and so only the patent holder, or their licensees, have the rights to sequence that DNA during the patent's life.



In addition, so-called "patent thickets," where multiple patent holders stake their claims across the genome, could have the potential to inhibit the translation of genetic discoveries into health care benefits. Patent thickets have occurred in other technological domains when multiple patent holders have related claims; for example in consumer electronics or standards for digital video and music.



In April 2010 the Secretary's Advisory Committee on Genetics, Health and Society published a report, Gene Patents and Licensing Practices and Their Impact on Patient Access to Genetic Tests. Resting on the underlying assumption that patents on human genes were acceptable, the report recommended that diagnostic (but not therapeutic) genetic tests, be exempted from patent infringement, along with a research use exemption. Exempting diagnostic patents from infringement while still recognizing that diagnostic gene patents could exist was greeted with controversy at the time, especially considering that the case studies that accompanied the report showed mixed evidence of harm to patients as a result of gene patents.