| Term | Definition | |------|------------| | Epigenetics | The study of heritable changes in gene expression that do not involve changes to the underlying DNA sequence | | DNA Methylation | Addition of a methyl group to DNA, typically repressing gene transcription | | Histone Modification | Chemical changes to histone proteins that can affect gene expression | | Chromatin | Complex of DNA and proteins (primarily histones) that forms chromosomes | | CpG Islands | Regions of DNA where cytosine and guanine nucleotides are clustered | | Gene Silencing | Repression of gene expression | | Imprinting | Epigenetic phenomenon where certain genes are expressed in a parent-of-origin-specific manner | | Transgenerational Epigenetic Inheritance | Transmission of epigenetic marks across generations | | Epigenome | The complete set of epigenetic modifications on the genetic material of a cell | | Acetylation | Addition of an acetyl group to histones, generally associated with increased gene expression | | Demethylation | Removal of methyl groups from DNA or histones | | Histone Deacetylase (HDAC) | Enzyme that removes acetyl groups from histones | | DNA Methyltransferase (DNMT) | Enzyme that adds methyl groups to DNA | | Non-coding RNA | RNA molecules that are not translated into proteins but can regulate gene expression | | Epigenetic Reprogramming | Erasure and reestablishment of epigenetic marks during development | | Heterochromatin | Tightly packed form of DNA, associated with inactive genes | | Euchromatin | Loosely packed form of DNA, associated with active genes | | Epimutation | Heritable change in gene expression without a change in DNA sequence | | Metastable Epiallele | Allele that can be expressed in different ways due to epigenetic modifications | | Epigenetic Drift | Accumulation of epigenetic changes over time, often associated with aging | #biology #genetic #health #cheatsheet