What is the Origin of DNA Methylation?

The term combines 'DNA,' the abbreviation for deoxyribonucleic acid, and 'methylation,' the chemical process of adding a methyl group. This epigenetic phenomenon was discovered in the mid-20th century, with its role in gene silencing and embryonic development becoming clearer in subsequent decades. Its use as a biomarker for biological age has recently brought it to the forefront of longevity research.

What is the Mechanism of DNA Methylation?

When methylation occurs in a gene's promoter region, it often acts as a molecular switch, typically leading to gene silencing by blocking the binding of transcription factors. Conversely, demethylation can activate gene expression. The enzymes DNA methyltransferases (DNMTs) and ten-eleven translocation (TET) enzymes govern this dynamic process, with their activity being sensitive to nutritional factors and environmental stressors, thereby linking lifestyle to gene regulation.

DNA Methylation ∞ Area

DNA Methylation

Meaning

DNA methylation is a critical epigenetic mechanism involving the addition of a methyl group to the cytosine base of DNA, typically occurring at CpG sites. This biochemical modification does not alter the underlying DNA sequence but profoundly affects gene expression by influencing the accessibility of the genetic material. It is a key regulator of cellular differentiation, genomic stability, and is a measurable hallmark of biological aging.