The decision is narrower than it is made out to be in this thread. There are many prongs that must be met for something to be patentable. This decision is about patentable subject matter: whether an isolated DNA sequences are the kind of thing that can be patented (irregardless of whether any particular DNA sequence is deserving of a patent). This decision says that an invention is not automatically non-patentable just because it is an isolated DNA sequence.

Therefore, some of the points being raised in this thread fall outside the scope of the decision. For example, you can't patent certain chemical compounds which are naturally occurring. Those patents fail not on the subject matter bar (because chemical compounds are patentable subject matter) but on the novelty bar (because naturally occurring compounds are not novel). It's quite possible that the lower court will find that Myriad's patents fail on that ground.

It's worth reading the decision itself, here: http://www.cafc.uscourts.gov/images/stories/opinions-orders/....

It's pretty well-written and should be digestible for lay-people. The background starts on page 6. The claims start on Page 9. A basic background on genetics starts on page 10. The discussion on declaratory judgment jurisdiction can be skipped, and the analysis of whether isolated genes are patentable subject matter starts on page 36. An important discussion of what is NOT the subject of the appeal starts on page 37. In particular:

"Before reviewing the applicability of the Supreme Court’s Mayo holding to the claims of the Myriad patents, however, it is important to state what this appeal is not about... The question is also not whether is it desirable for one company to hold a patent or license covering a test that may save people’s lives... Those questions are not before us. It is solely whether the claims to isolated BRCA DNA, to methods for comparing DNA sequences, and to a process for screening potential cancer therapeutics meet the threshold test for patent-eligible subject matter under 35 U.S.C. § 101 in light of various Supreme Court holdings, particularly including Mayo. The issue is patent eligibility, not patentability." (p. 37).

In order to be patentable, an invention must meet various requirements. One of those requirements is having patentable subject matter. It is a necessary, but not sufficient, criterion of patentability.

There were three questions before the court: whether two types of isolated gene sequences were not patentable subject matter, and whether Myriad's method of comparing genes against "known bad" genes was patentable subject matter. The court decided that the isolated gene sequences were patentable subject matter but that the comparison method was not. It punted on the policy question of whether gene patents were desirable:

"But disapproving of patents on medical methods and novel biological molecules are policy questions best left to Congress, and other general questions relating to patentability and use of patents are issues not before us. As will be seen, on the limited questions before us, we conclude that the composition claims and the screening claim involving growing a transformed host cell meet the standards for patent eligibility, while the claimed methods for “analyzing” or “comparing” do not." (p. 38).

The heart of the decision is on page 38-39. It basically argues that the "isolated gene sequences" as distinguished from the genes themselves, are patentable, just as any man-made chemical compound is patentable:

"The principal claims of the patents before us on remand relate to isolated DNA molecules... They are claims to compositions of matter, expressly authorized as suitable patent-eligible subject matter in § 101. As to those claims, the issue of patent-eligibility remains, as it was on the first appeal to this court, whether they claim patent-ineligible products of nature. We hold that they do not. The isolated DNA molecules before us are not found in nature. They are obtained in the laboratory and are man-made, the product of human ingenuity. While they are prepared from products of nature, so is every other composition of matter. All new chemical or biological molecules, whether made by synthesis or decomposition, are made from natural materials. For example, virtually every medicine utilized by today’s medical practitioners, and every manufactured plastic product, is either synthesized from natural materials (most often petroleum fractions) or derived from natural plant materials. But, as such, they are different from natural materials, even if they are ultimately derived from them. The same is true of isolated DNA molecules." (p. 38-39).