Addition of methyl groups to cytosine, usually silencing gene expression.
DNMTs add methyl groups to CpG cytosines; promoter CpG islands that are methylated are silenced. Methylation patterns are copied during replication by DNMT1 and altered in development and cancer.
It underlies imprinting and X inactivation.
Addition of methyl groups to cytosine, usually silencing gene expression.
DNA Methylation is one of the 52 topics in Molecular Biology. It is rated Intermediate, so it suits learners who already know the core vocabulary. Related topics in this area include microRNA, Histone Modification, Mutation and Repair Link.
Tumour suppressor genes are often hypermethylated in cancers.
Work through the Beginner topics in Molecular Biology first, such as Central Dogma, DNA Replication, Base Pairing, then return to DNA Methylation. Intermediate topics assume the Beginner vocabulary.
The closest topics to DNA Methylation are microRNA, Histone Modification, Mutation and Repair Link, Chromosome Territories. Comparing them side by side is a good way to see how the ideas connect.
Read the summary and the in-depth section, then use the quick check on the interactive lesson for DNA Methylation. To practise the whole of Molecular Biology, use the Molecular Biology quiz.
DNA Methylation: Addition of methyl groups to cytosine, usually silencing gene expression. microRNA: About 22-nucleotide RNAs that fine-tune gene expression by blocking translation or promoting mRNA decay. Read both side by side and note what each one explains.
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with microRNA and explain the difference aloud. Finally, take the Molecular Biology quiz and come back to this page for any question you miss.
About 22-nucleotide RNAs that fine-tune gene expression by blocking translation or promoting mRNA decay.
🧫 Molecular BiologyAcetylation, methylation and phosphorylation of histone tails alter chromatin openness and gene activity.
🧫 Molecular BiologyUnrepaired DNA damage becomes permanent mutation after replication, driving cancer and ageing.
🧫 Molecular BiologyIndividual chromosomes occupy distinct regions of the nucleus, influencing genome organisation and expression.
🧫 Molecular Biology