if the four basic nucleobases decide gene outcome (ACGT), but have strict complementary base pairing (A-C & G-T), are there then four values to variate with or just two, like binary?

Question

**Correction**: A-T & C-G, not ~~A-C & G-T~~
The question arose from [here](https://www.reddit.com/r/Showerthoughts/comments/k3b4ba/just_like_computers_speak_in_binary_1s_and_0s_the/ge2jzil?utm_source=share&utm_medium=web2x&context=3), where I compared binary code to human DNA’s ACGT, then someone who knows more about IT than me made a good question.

If it’s not clear what I’m asking yet:
in binary you can have a lot of variation with the values 1 and 0
in human DNA (if we ignore RNA and (U)racil for now) there are four values, A, C, G, T. But since they bind strictly A-C & G-T doesn’t that technically leave DNA with only two factors to variate with?

Like: ~~A-C, A-C, G-T, A-C~~ A-T, A-T, C-G, A-T
Instead of: AGTATAC

In: Biology

Answer 1

It is not binary. Genetic code is interpreted as codons, groups of three nucleotides coding for one amino acid. A codon “ATT” codes for isoleucine, while “CTT” codes for leucine. This would not be the case if it was “binary”.

Indeed, DNA is actually split into two strands for transcription. A nucletiode pair is never read for transcription, only a strand of single nucleotides.

ATGATAC could be grouped into codons three different ways:
ATG_ATA_C, A_TGA_TAC and AT_GAT_AC. Each of these is called a reading frame. To add to the fun, the strand has a complementary strand, which would be CGTCGCA. DNA is directional, so that would be read from the opposite direction, in effect being ACGCTGC. And that, in turn, could be read in three different reading frames. In the end, each piece of DNA could be read in six different ways.