Monday 19 May 2008

A, C, G, T

‘The filament of DNA is information, a message written in a code of chemicals, one chemical for each letter. It is almost too good to be true, but the code turns out to be written in a way that we can understand. Just like written English, the genetic code is a linear language, written in a straight line…it is digital, in that every letter bears the same importance. Moreover, the language of DNA is considerably simpler than English, since it has an alphabet of only four letters, conventionally known as A, C, G and T… how few people even guessed such a possibility. For the first half of the twentieth century, one question reverberated unanswered through biology: what is a gene? It seemed almost impossibly mysterious.’ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000

‘The amino acids (the monomers) are just like the letters in a font of type. The base of each letter from the font is always the same, so that it can fit into the grooves that hold the asembled type, but the top of each letter is different, so that a particular letter will be printed from it...for each protein the letters have to be in a particular order (as indeed they have to be in a particular paragraph).’ Francis Crick, Co-discoverer of the structure of DNA, What Mad Pursuit, Weidenfeld & Nicolson, 1989

‘How are the instructions written in the DNA? DNA is a code. The English alphabet is also a code.. Let's take the word "koala". The word as it is typed on the screen is not actually a koala. It doesn't live in Australia or eat eucalyptus leaves. But the letters 'k', 'o', 'a', 'l' and 'a' in that particular order mean an animal that lives in Australia and eats eucalyptus leaves.’ YourGenome.org

‘…genomes are written entirely in three-letter words, using only four letters: A, C, G and T (which stand for adenine, cytosine, guanine and thymine). And instead of being written on flat pages, they are written on long chains of sugar and phosphate called DNA molecules…The genome is a very clever book because in the right conditions it can both photocopy itself and read itself. The photocopying is known as replication, and the reading as translation.’ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000

‘And the Word was made flesh, and dwelt among us.’ John 1, The Bible

‘O wisdom truly perfect! Thus to call/ From a few causes such a scheme of things, / Effects so various, beautiful, and great…’ James Thomson, 1700-48, To the Memory of Sir Isaac Newton


A, C, G, T

We have sung our song
a million billion times –

and know not why we sing -
conductor and Word are one.

Rehearsing ourselves until we were -
learning life’s words; from ourselves

we laid the recipes inside the heart
we learned to make. We were mad

with the smell of creation - the songs
of our making filled the whole world,

for we had no limits; we could not stop
or rest for the Word can never be silent.

Rehearsing our worms in mud,
our lung and peacock feather -

until our chemical art
formed hand and eye.

Four billion years we have sung
to make you, just so you can be -

creation is its own infinite purpose.
We believe the voice that called us

is creation; understanding our works,
we believe that Word must be love.

No comments: