We didn&#x27;t learn any of those things because of genomics. The major cancer therapies of today were developed before short read sequencing was even a thing; cancer researchers been saying for decades that cancer is &quot;not one disease&quot;. In fact the genomics efforts were largely intended to overturn that wisdom by using genetic lesions to unify disparate cancer types (to little avail). About the only really interesting thing we learned from these recent efforts is that tumors are a lot more genetically heterogeneous than we previously appreciated, which just expands the problem space.<p>The proof in the pudding is this: you can get your exome sequenced today and report hundreds of tumor variants, but there is a bare handful of variants that will result in a change in your treatment, and most of those lesions were well-studied before genomics took off.<p>&gt;We very clearly understand gene expression and signal transaction to a first order, and have bits of the second order down too. There might be more - but that doesn&#x27;t make that first order inneffective or wrong.<p>Yes, in fact, our first order understanding IS ineffective. This is what I study every day, so perhaps I&#x27;m too close to this, but we literally do not understand the effect of most (99.9%) of genetic variants on gene expression. Sure, there&#x27;s lots you can do with a first order understanding, but materially, what happens when you sequence a tumor (or a germline, for that matter), is that researchers get a list of mutations, stare at it mystified for a while, and then shrug and move on, because there&#x27;s really nothing you can do to understand what these things mean.<p>Yes, this stuff is the way of the future, and it&#x27;s important to do it for our greater knowledge and understanding in the future. But we&#x27;re far, far away from this point right now.