Genomics Step by Step Michael Roberts

 I have dipped into genetics a few times over the years and found the terminology frustratingly opaque.  What is an allele, can we see it ?  There seemed to be elements with names but without clear functions.  Terms such as 'junk DNA' made me suspicious, was it really junk ?  We can see chromosomes but what about genes ?  And how do they sit with chromosomes ?

Increasingly I have read about genetic testing.  I heard that a Siberian Lesser Whitethroat was confirmed as such by sequencing the cytochrome b gene from a feather sample last year; this was a first for my home county of Cumbria.  But why that gene ?

A search online produed a lucky find.  This book was published in 2025.

The field of genomics (so called because it deals with the entire sequencing of base pairs rather than looking simply at genes) is advancing fast.  It has grown alongside IT improvements as it relies heavily on data analysis.

The book is arranged in chapters and while the author tells us that we can dip in at any point, I think a systematic work through is essential.  This is particularly so for readers without a good grounding in contemporary genomics.

It is very systematically layed out, it's not chatty, there are no anecdotes but is is very clear.  The groundwork is layed out in advance of the more complex aspects such as medical applications and ethical implications.

One thing that has always puzzled me is that the human genome project was completed in 2003.  But whose genome was sequenced ?  There is no single genome as we are all genetically different.  Well, it turns out that the first genome to be fully sequenced was that of James Watson a few years later.  Yes, that same Watson who discovered the double helix along with Francis Crick.

Another interesting revelation is around that of the formerly named 'junk DNA'.  Unsurprisingly, this is no junk; it influences the expression of genes.  It turns genes on and of and amplifies and supresses them.  This is an absolutely vital function.  So many conundrums become clear.  This is not to say that everything is now understood.  Michael Roberts makes it very clear that cetain elements and functions are still not fully understood.

I now understand that a gene is a discreet section of a chromosome, it has a start point and an end stop along the chain of DNA that is the double helix.

It is all so elegant and the book explains that elegance with great simplicity.