epigenetics

Epigenetics

The study of heritable changes in gene expression or cellular phenotype that do not involve changes in the DNA sequence.

Gene Expression Regulation

Epigenetic modifications affect how genes are turned on or off, influencing development and disease.

DNA Methylation

Addition of a methyl group (-CH3) to DNA, usually silencing gene expression.

Histone Modification

Changes to histones that affect the tightness of DNA packaging, influencing gene accessibility.

Acetylation

Histone acetylation usually activates gene expression by loosening DNA packaging.

Histone Methylation

Can either activate or repress gene expression depending on context.

CpG Sites

Regions where cytosine is followed by guanine, where DNA methylation predominantly occurs.

Nucleosome Remodeling

Process where histone modifications lead to nucleosome sliding, affecting gene expression.

Agouti Gene

Gene that exhibits epigenetic modifications impacting fur color in mice, correlated with methylation levels.

Environmental Factors

Elements like diet, toxins, and stress that can influence epigenetic modifications.

Stem Cell Differentiation

Process where epigenetics plays a role in different cells expressing distinct genes despite identical DNA.

Cancer and Epigenetics

Abnormal epigenetic modifications leading to diseases like cancer, affecting genes related to cell growth or apoptosis.