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 
Review by Brian Clegg

Comments

Popular posts from this blog

Bits to Bitcoin - Mark Stuart Day ***

When I saw the title of this book, I got all excited - at last we were going to get an explanation of bitcoin for the rest of us, who struggle to understand what the heck it really involves. There certainly is an explanation of bitcoin, but it comes in chapter 26 - in practice, the book contains far more. Almost every popular computer science title I've read has effectively been history of computer science - this is one of the first examples I've ever come across that is actually trying to make the 'science' part of computer science accessible to the general reader.

I don't mean by this that it's an equivalent of Programming for Dummies. Instead, Bits to Bitcoin takes the reader through the concepts lying behind programming. If we think of programming as engineering, this is the physics that the engineering depends on. This is a really interesting proposition. Many years ago, I was a professional programmer, but I never studied computer science, so I was only fa…

How to Speak Science - Bruce Benamran ***

I can't remember a book where my mental picture of what the star rating would be has varied so much. At first glance, it looked like a solid 4 star title. It looks fun (despite the odd title - it sounds like it's a book on public speaking for geeks) and a flick through showed that it covers a huge amount of science topics, mostly physics - so it was promising as a beginner's overview. There is one small issue to be got out of the way on the coverage side. There's a whole lot of physics, with a gaping hole that is quantum theory. More on that later.

After reading a few pages, I had to downgrade that score to 3 stars because of the writing style. It oozes smugness. All became clear when I read the words 'For those of you who aren't familiar with my YouTube channel.' How to Speak Science reads like a transcript of a YouTube rant. The reason I love reading books and can hardly ever be bothered to watch videos is to get away from this kind of thing. However, I ac…

By the Pricking of Her Thumb (SF) - Adam Roberts *****

Sometimes a sequel betters the original - think Terminator 2 - and Adam Roberts has done this with his follow-up to The Real-Town Murders. (It's sensible to read the first book before this: while it's not essential, there are plenty of references you will miss otherwise.)

Ostensibly this is a murder mystery, or, as Roberts tells us, a combination of a howdunnit and a whodunnit-to, as the central character Alma is called on to work out how someone found with a needle stuck through her thumb was killed and which of a group of four super-rich individuals is dead when all claim to still be alive - though one of the group who hires Alma is convinced that the death has occurred. 

However, this is anything but a conventional murder mystery - far more so than the strange crimes suggest. Alma and her partner Marguerite (the latter still trapped by an engineered polyvalent illness that requires treatment every 4 hours and 4 minutes) don't do a lot of detecting. In fact Marguerite hard…