DNA

Free flowing, attractive and attacking football is in the DNA of Birmingham City FC. 

There are quite a few inaccuracies in that statement. But not to worry as the term DNA has now been used as a marketing gimmick or metaphorical shorthand for a few years now.

Let’s get the basic bits out of the way:

DNA stands for Deoxyribonucleic acid and it is the only molecule capable of reproducing itself. DNA is present in almost all living cells of all living things. Only DNA, and no other molecule, carries the ability to copy and then pass heritable information to subsequent generations.

The famous double helix structure consists of two strands of DNA combining a bit like a spiral staircase. Sugars and phosphates make up the sides and base pairs make up the middle or rungs. Base pairs are the compounds adenine (A), cytosine (C), guanine (G) and thymine (T). Crucially, adenine (A) pairs only with thymine (T), and cytosine (C) only pairs with guanine (G). Only the pairs of either A:T or C:G fit as rungs between the two siderails.

The difference between human DNA and tomato DNA is the sequence of DNA base pairs A, T, C, and G. A common analogy used in introductions to this subject is that two different recipes in an English language cookbook may use the same 26 letters to make words but differ in the exact sequence of those same 26 letters, resulting in different recipes.

The differences, although small, can have dramatic consequences. Your DNA sequence determines your basic blood type (A, B, AB, or O), hair and eye colour, whether your earlobes dangle, and whether you can roll your tongue.

But where to go after that very brief overview? Just a couple of weeks ago I was reading this by Alison George in the New Scientist:

Ancient human DNA found on cave art for the first time. DNA from ancient humans has been found on a prehistoric cave painting and on cave walls, demonstrating the potential to one day identify individual artists and resolve the debate over Neanderthals' artistic abilities. She was writing about samples from 5,000 to 17,000 years ago.

Police now use DNA to identify long forgotten cold cases but the first use of DNA in an ongoing investigation occurred in Britain in 1986. Professor Alec Jeffreys was assisting the British police in solving two separate rape-murders and was able to prove that the man arrested was not guilty.

Historians use DNA to identify the remains of lost soldiers, from WWI infantry missing in action at Vimy Ridge to King Richard III under a car park in Leicester.

The popularity of DNA is reflected in the rise of direct-to-consumer DNA testing. For a relatively small fee, several companies will conduct a DNA analysis from the cells in your cheek swab or spit sample. However, these DNA tests are not 100 per cent accurate.

Molecular geneticists have learned not only how to read the information carried by a DNA strand, but also how to edit or supplement it. These innovations allow development of a number of commercial products such as insulin and cheese.

Much of the above was taken from an article on the BBC Science Forum by Dr Alan McHughen published on October 18, 2020.

I do feel there should be a bit of romance in DNA. This was written a few years ago.

Anniversary Road
(for the Horrocks family)

Back home
the kids probably think
you’re settling for tea
and a nice gateaux
in the boring café
of another boring gallery.

And if they were around
they’d be right,
mostly,
a touch of your fingers
hidden from a groan
of embarrassed teenagers.

But not this year
this aisle of months
leading away from silver
this is for you
twenty six years

and a letter from every one.

Amsterdam was holding hands
keeping out the cold
on the Keizersgracht Canal.
Bruges was kissing
under the tartan blanket
of a horse-drawn carriage.

Calais is a secret
that only two can share
arms linked by a window
a double helix in a single room
a bond that’s for life
discussing Dundee or Dresden.

First published in ‘away’, 2010.

Thanks for reading, Terry Q.