Skip to main content

Junk DNA - Nessa Carey ****

What grabs the reader fairly early on in Junk DNA is just how wonderfully complex and sophisticated the biological machinery in our cells is. As a non-biologist, I found that reading her description of the way that the cellular mechanisms pull the two copies of a chromosome to opposite sides of the cell, for instance, absolutely riveting. But it's not all superbly functioning miniature marvels: Nessa Carey also explores the many ways that these genetic mechanisms can go wrong. Anyone who ascribes the complexity of biological systems to a designer needs to contemplate just what a messy, over-complex and ad-hoc design has emerged.

I really hadn't though of there being a mechanism for separating copies of chromosomes before - and I think this is the beauty of Carey's book. Us non-biologists have some vague idea of how cells split or proteins are assembled from the genetic 'instructions', but there's a whole host of mechanisms required to go from an apparently simple concept to making it happen, and this really opens up in Junk DNA.

I mentioned how things go wrong. As genetic medical conditions are often a key to unlocking the secret of a cellular mechanism, there is a lot about genetic failures here, some very distressing - I'm personally not a great enthusiast for things medical (I can't even watch Casualty, let alone 24 Hours in A&E), but in this context it at least wasn't gratuitous.

Of course, as the name suggests, at the heart of the book are all the bits of our DNA - the vast majority of the content of our chromosomes - that aren't genes. In her previous book, The Epigenetics Revolution, Carey had already introduced us to some of the workings of what was once referred to as 'junk DNA' - specifically how parts of it turn various genes on and off, effectively acting as the controls that work the mechanisms specified by our genetic blueprints - but in this new book we see many more processes, capabilities, wonders and failings of the super-genetic parts of the system.

I do have a couple of niggles. This is a topic that lends itself to metaphor and simile - I did it without even noticing in the previous paragraph, but Carey plunges into metaphorical mode at the slightest opportunity, and some of her similes are a little painful - when she brings in the movie Trading Places or a Bugatti Veyron, for instance, the process seems forced. (Even the subtitle is a metaphor of sorts.) Also slightly irritatingly, several times she refers to the human appendix as having no function - if she'd read my Universe Inside You, she'd have known that this concept, like classifying all DNA that doesn't code for proteins as junk, went out some time ago (the appendix does have a useful function as a kind of respite centre for friendly bacteria from the wild conditions in the stomach).

The other issue, which I also referred to in my review of The Epigenetics Revolution, and similar to the complaint I had about I, Superorganism is that we end up in Rutherford's 'all science is either physics or stamp collecting' territory. While some the mechanisms themselves are truly fascinating, when the reader gets bogged down in the detail it can begin to seem that there is far too much cataloguing and not enough narrative. Carey has usefully responded to reviews of the previous book by often moving the name of a gene into a footnote, but it doesn't prevent the feeling of drowning in labels when you read something like:
Where C is followed by G in our genome, the C can have a small modification added to it. This is most likely to happen in regions where this CG motif is present in high concentrations. The large number of CCG repeats in the Fragile X expansion provide exactly this environment.
This is by no means the most concentrated example of labellitis, and typical of quite a lot of the text. In the end I was happy to think 'It goes with the territory, live with it.' There is still so much fascinating material in here that it is well worth ploughing through the biological wordfest.


Hardback 

Kindle 
Using these links earns us commission at no cost to you
Review by Brian Clegg

Comments

Popular posts from this blog

The Infinity Machine - Sebastian Mallaby ****

It's very quickly clear that Sebastian Mallaby is a huge Demis Hassabis fan - writing about the only child prodigy and teen genius ever who was also a nice, rounded personality. After a few chapters, though, things settle down (I'm reminded of Douglas Adams' description of the Hitchhiker's Guide to the Galaxy ) and we get a good, solid trip through the journey that gave us DeepMind, their AlphaGo and AlphaFold programs, the sudden explosion of competition on the AI front and thoughts on artificial general intelligence. Although Mallaby does occasionally still go into fan mode - reading this you would think that AlphaFold had successfully perfectly predicted the structure of every protein, where it is usually not sufficiently accurate for its results to have direct practical application - we get a real feel for the way this relatively unusual company was swiftly and successfully developed away from Silicon Valley. It's readable and gives an important understanding of...

In Seach of Sea Dragons - Matthew Myerscough ****

It's common advice to would-be authors of narrative non-fiction to open with something dramatic - Matthew Myerscough certainly does this with the story of his being trapped under an avalanche on Snowdon (while his girlfriend, also carried away remains on top of the snow unhurt). It certainly is dramatic, but seemed entirely disconnected from the reason I got the book, which was to read about fossil collecting.  Luckily, though, in the second chapter we get into a more conventional 'how I got interested in fossils as a boy'. Having recently reviewed Patrick Moore's autobiography and noting that astronomy was one of the few sciences where amateurs can still make a contribution, it came to mind that palaeontology is another - Myerscough is a civil engineer by trade, but just as amateur astronomers can find new details in the skies, so amateur fossil hunters have been searching for these relics for centuries. When I give talks in junior schools, the two topics that guarant...

Robot-Proof - Vivienne Ming ****

As Vivienne Ming makes apparent, there seem largely to be two views of AI's pros and cons, both of which are almost certainly wrong. It's either doom-saying 'It'll destroy life as we know it' or Pollyanna-ish 'It'll do all the boring work and we can all be wonderfully creative and live lives of leisure.' Instead, Ming gives us a clear analysis of the likely trajectory for the workplace, particularly for the IT industry. She describes three 'equally flawed, intellectually lazy strategies' to deal with the impact of AI. The first is substitution and deprofessionalisation, using AI to allow cheaper 'AI-augmented technicians' to replace more expensive professionals, producing more low wage jobs and fewer mid-range. This does save money but leaves a company at risk of being easily outcompeted. The second is what Ming describes as the '"A-Player" Hunger Games', the approach favoured by Silicon Valley. This sees the growing rif...