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Biologists tend to be a rather restrained social group when it comes to disagreements. There’s the occasional aggressive question-and-answer session at a conference but generally public pronouncements are carefully phrased. This is especially true of anything that is published, rather than said at a meeting. We all know how to read between the lines, of course, as shown in Figure 14.6 but typically, published papers are carefully phrased. That’s what made the debate that followed ENCODE particularly entertaining to the relatively disinterested observer.

The most forthright responses were mainly from evolutionary biologists. This wasn’t altogether surprising. Evolution is the biological discipline where emotions tend to run highest. Normally the bullets are targeted at creationists, but the Gatling guns may also be turned on other scientists. Epigeneticists working on the transmission of acquired characteristics from parent to offspring were probably quite relieved that ENCODE took them out of the firing line for a while.{281}

Figure 14.6 Scientists are usually outwardly polite (left-hand statements), but are sometimes just speaking in barely disguised code (right-hand thoughts) …

The angriest critique of ENCODE included the expressions ‘logical fallacy’, ‘absurd conclusion’, ‘playing fast and loose’ and ‘used the wrong definition wrongly’. Just in case we were still in doubt about their direction of travel, the authors concluded their paper with the following damning blast:

The ENCODE results were predicted by one of its lead authors to necessitate the rewriting of textbooks. We agree, many textbooks dealing with marketing, mass media hype, and public relations may well have to be rewritten.{282}

The main criticisms from this counter-blast centred around the definition of function, the way that the ENCODE authors analysed their data, and the conclusions drawn about evolutionary pressures. The first of these applied to the problems we have already described, using our Jackson Pollock and Downton Abbey analogies. In some ways, these problems derive in large part from difficulties in separating mathematics from biology. The ENCODE data sets were predominantly interpreted by the original authors through the use of statistical and mathematical approaches. The sceptics argue that this leads us down a blind alley, because it doesn’t take into account biological relationships, and that these are critically important. They use a very helpful analogy to explain this. The reason the heart is important is that it pumps blood around the body. That’s the biologically important relationship. But if we analysed the actions of the heart just by a mathematically derived map of its interactions, we would draw some ridiculous conclusions. These could include that the heart is present so that it can add weight to the body, and to produce the sound ‘lub-dub’. These are both things that the heart undoubtedly does, but they are not its function. They are just contingent on its genuine role.

The authors criticised the analytical methods because they felt that the ENCODE teams had not been consistent in the way they applied their algorithms. One consequence of this was that effects seen in a large region might weigh down an analysis inappropriately. For example, if a block of 600 base pairs was classified as being functional, when all the work was actually carried out by just ten of them, this would dramatically skew the percentage of the genome that would be designated as having a function.

The evolutionary argument was that the ENCODE authors ignored the standard model that regions with large amounts of variation are reflective of a lack of evolutionary selection, which in turn means they are relatively unimportant. If you want to overturn such a long-held principle, you need to have very strong grounds for doing so. But the critics claimed that the ENCODE papers, although containing huge amounts of data, had only focused on an inappropriately small number of regions when drawing evolutionary conclusions from the sequences of humans and other primates.

There are interesting scientific arguments on both sides, but it would be disingenuous to believe that the amount of heat and emotion generated by ENCODE has been purely about the science. We can’t ignore other, very human factors. ENCODE was an example of Big Science. These are typically huge collaborations costing millions and millions of dollars. The science budget is not infinite and when funds are used for these Big Science initiatives, there is less money to go around for the smaller, more hypothesis-driven research.

Funding agencies work hard to get the balance right between the two types of research. In many cases, Big Science is funded if it generates a resource that will stimulate a great deal of other science. The original sequencing of the human genome would be a clear example of this, although we should recognise that even that was not without its critics. But with ENCODE the controversy is not around the raw data that were generated, it’s about how those data are interpreted. That makes it different from a pure infrastructure investment in the eyes of the critics.

When all stages and aspects of ENCODE are added up, it cost in the region of a quarter of a billion dollars. The same amount of money could have funded at least 600 average-sized single research grants focusing on investigation of individual hypotheses. Choosing how to distribute funding is a balancing act, and at these levels of funding it is guaranteed to create division and concern.

A company called Gartner created a graphic that shows how new technologies are perceived. It is known as the Hype Cycle. At first everyone is very excited — ‘the peak of inflated expectations’. When the new tech fails to transform everything about your life there is a crash leading to the ‘trough of disillusionment’. Eventually, everyone settles down, there is a steady growth in rational understanding and finally a productive plateau is reached.

With something like ENCODE this cycle is extraordinarily compressed, because of the polarisation from the most vocal groups. Those scientists with inflated expectations are operating at exactly the same time as those in the trough. Pretty much everyone else is pragmatic, and will use the data from ENCODE when it is useful to do so. Which is usually when it can help inform a specific question that an individual scientist finds interesting.

15. Headless Queens, Strange Cats and Portly Mice

The ENCODE consortium identified a daunting abundance of potentially functional elements in the human genome. Given the huge numbers, it’s hard to define a sensible strategy for deciding which candidate regions to experiment on first. But the task may not be quite as difficult as it seems, and that’s because, as always, nature has decided to point the way. In recent years scientists have begun to identify human diseases that are caused by tiny changes to regulatory regions of the genome. Previously, these might have been dismissed as harmless random variations in junk DNA. But we now know that in some cases just a single base-pair change in an apparently irrelevant region of the genome can have a definite effect on an individual. In rare cases, the effect is so severe that life itself is impossible.

We’ll start with a less dramatic example, but one that takes us back about 500 years, to the reign of King Henry VIII in England. Most British schoolchildren are at some point taught a useful rhyme to help them remember what happened to the six wives of this notorious monarch: