Definition
Modifications to DNA structure that do not alter the DNA sequence but can affect gene expression and an individual’s phenotype. Some epigenetic modifications can be inherited, while others are acquired throughout life.
Use in clinical context
DNA contains all the information needed to grow and maintain an individual. Not all the information is needed at the same time, however. Epigenetic changes to DNA influence gene expression – turning genes on or off. This is done by allowing or preventing transcription, often physically making part of the genome accessible or inaccessible. Epigenetic changes can be responsible for proteins being made at the wrong time, or not made when required.
Related terms
Deoxyribonucleic acid (DNA) | Gene | Gene expression | Genome | Phenotype | Protein | Sequence
