Commenters posting about how obvious this result should be- since <i>we know</i> living systems are a huge mess of hacks where anything could happen- have a point, but perversely, this kind of point may be harder for trained biologists to swallow than ordinary readers.  In trying to make sense of deeply complicated systems, using extremely limited experimental data, &quot;educated guesses&quot; such as &quot;a given gene has some specific function&quot; are a tremendous aid in generating useful conclusions.  The scientists who use these heuristics are smart people who know what they&#x27;re doing- they know that their assumption will be faulty in some cases, but even if their conclusions are <i>usually</i> true, these studies are of great use.  What a result like the one in this article tells us is that this particular assumption wasn&#x27;t only sometimes faulty, it was <i>counter-intuitively</i> faulty.  As background context for future studies, alone, this sort of information is invaluable.<p>One might argue that we should try to excise assumptions like these from biology altogether, since we&#x27;ve seen them so often be wrong.  But we&#x27;re dealing with the messy physical world here- making conclusions about the world based on limited empirical data cannot be done without taking some underlying rules for granted.  For instance, note that this study also makes assumptions- namely, that the <i>in vitro</i> behavior of these protein isoforms they produce are indicative of <i>in vivo</i>.  There are good reasons to suspect that this wouldn&#x27;t be the case!  But our methods are still so limited that we believe we&#x27;re better off taking this assumption-laden evidence on face value.