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
Labels:

Comments

Post a Comment

Popular posts from this blog

The Decline and Fall of the Human Empire - Henry Gee ****

In his last book, Henry Gee impressed with his A (Very) Short History of Life on Earth - this time he zooms in on one very specific aspect of life on Earth - humans - and gives us not just a history, but a prediction of the future - our extinction. The book starts with an entertaining prologue, to an extent bemoaning our obsession with dinosaurs, a story that leads, inexorably towards extinction. This is a fate, Gee points out, that will occur for every species, including our own. We then cover three potential stages of the rise and fall of humanity (the book's title is purposely modelled on Gibbon) - Rise, Fall and Escape. Gee's speciality is palaeontology and in the first section he takes us back to explore as much as we can know from the extremely patchy fossil record of the origins of the human family, the genus Homo and the eventual dominance of Homo sapiens , pushing out any remaining members of other closely related species. As we move onto the Fall section, Gee gives ...
Post a Comment
Read more

The Autobiography – Charles Darwin ****

I have to confess to putting off reading this book until the last moment, as I expected it to be a typical piece of Victorian sentimental unreadable stodge. I was wrong. Darwin’s little book (only 150 small pages with appendices) was originally written for his own children, and displays a very personal style of writing – though, as son Francis comments, his style was always more populist than was common then: “In writing he sometimes showed the same strong tendency to strong expressions that he did in conversation. Thus in the Origin, p440, there is a description of a larvel [sic] cirripede ‘with six pairs of beautifully constructed natatory legs, a pair of magnificent compound eyes and extremely complex antennae’. We used to laugh at him for this sentence, which we compared to an advertisement.” The main book is delightful because it demonstrates Darwin’s self-depreciating modesty, and the fascinating path he took from enthusiastic shooter of game, to amateur geologist (still his...
Post a Comment
Read more

The Premonitions Bureau - Sam Knight ****

Not everyone would class this as popular science, but it concerns an attempt to take a scientific approach to paranormal abilities - notably premonitions (aka clairvoyance) and as such, it fits the category. Writing in the typical dramatic storytelling style of a US magazine, Sam Knight brings to life the remarkable tale of the work of two British figures from the 1960s. The central one is psychiatrist John Barker, with a supporting role given to newspaper and TV science reporter Peter Fairley. Barker had a long interest in extra sensory phenomena - the story takes off when he was inspired by a number of people claiming to have foreseen the Aberfan disaster (which terrible tragedy Knight covers movingly). As a result of the Aberfan premonitions, the pair were responsible for London's Evening Standard newspaper setting up a long-running experiment in the form of 'The Premonitions Bureau.' Aware that the Aberfan predictions were only reported after the event, and hence flawe...
Post a Comment
Read more