The CpG sites or CG sites are regions of DNA where a cytosine nucleotide is followed by a guanine nucleotide in the linear sequence of bases along its 5' → 3' direction. CpG sites occur with high frequency in genomic regions called CpG islands. Cytosines in CpG dinucleotides can be methylated to form 5-methylcytosines.

A CpG site is a region in the DNA sequence where cytosine is followed by guanine in a specific direction. These sites can be methylated and are categorized into two classes based on CpG concentration, with CpG islands being one of them.

Methylated cytosines are found primarily at CpG dinucleotides, but are also found at non-CpG sites (CpA, CpT, and CpC). The general functions of CpG and non-CpG methylation include gene silencing or activation depending on the methylated regions.

A CpG site on a genome is the term applied to cytosine and guanine appearing consecutively on the same strand of nucleic acid (the "p" stands for the phosphodiester bond joining the two nucleotides).

The majority of mammalian gene promoters are encompassed within regions of the genome called CpG islands that have an elevated level of non-methylated CpG dinucleotides. Despite over 20 years of study, the precise mechanisms by which CpG islands ...

Aug 2, 2024 · CpG islands are unique DNA sequences that are characterised by their high GC content and abundance of CpG dinucleotides. These islands are typically found in the promoter regions of genes, which are crucial for controlling gene expression.

Oct 18, 2022 · CpG islands are typically common near transcription start sites and may be associated with promoter regions. Normally a C (cytosine) base followed immediately by a G (guanine) base (a CpG) is rare in vertebrate DNA because the Cs in …

Vertebrate CpG islands (CGIs) are short interspersed DNA sequences that deviate significantly from the average genomic pattern by being GC-rich, CpG-rich, and predominantly nonmethylated. Most, perhaps all, CGIs are sites of transcription initiation, including thousands that are remote from currently annotated promoters.

May 29, 2012 · Now, thanks to improved genome-scale mapping of methylation, we can evaluate DNA methylation in different genomic contexts: transcriptional start sites with or without CpG islands, in gene...

Feb 3, 2020 · DNA methylation alterations are related to multiple molecular mechanisms. The DNA context of CpG sites plays a crucial role in the maintenance and stability of methylation patterns.