[firefinch]

Wow! I did not expect much of a response, at least not so soon. Many of you who messaged me pointed out correctly that it's a string of DNA base pairs and gave me the sequence of the complementary strand. I'm not going to count this as an incorrect answer, BUT I am actually looking for a meaningful message in English! Here's a clue that might help you. Let's see :

Thymine had a little string- a string of DNA
Hidden in her genes it was, discretely tucked away
Thymine was a little slut, but to none had she confessed
And oh, she dearly wanted- that little string expressed

One day she decided to open up, to her friend polymerase
Who promptly unzipped her genes, with a coy smile on her face
No sooner was her cleavage bare, she gave a bashful grin
When a couple of friends dropped by, and decided to join in

Adenine, uracil and guanine decided to start the fun
Thymine paired with adenine, and it was long before they were done
But eventually they had to stop, when she cried UAA!
She soon had all her codons, and a string of RNA

When the string slid into the ribosomal groove, and all was said and done
She had finally expressed herself, and had a little fun.

-- firefinch