CpG island

So the, the main place where those methylation marks would be placed are, is in the promoter, right? In the promoter region of genes because this is where the polymerase comes in, sits, gets initiated, and will then transcribe the gene.

If that promoter region is not accessible because you put methylation marks there, like, they are always placed in a z- CG context because this is why they are called CpG islands.

So the C gets methylated, and it's always followed by a G, and you have those islands where many of those CpGs are present.

Wait, wait, wait.

Yeah

... down.

Um, the bottom line is we started with that string DNA, right? And you have some specs on top like the methylation groups, and those are typically, like in eukaryotes, for example, they are clustered around those CpG islands.

And if those CpG islands are close to a promoter, which means a region that enzymes can link to, then start making the gene into a protein basically.