Epigenetics: Heritable changes in gene expression that do NOT involve changing the underlying DNA sequence.
DNA Methylation: Adds methyl groups to DNA (Cytosine), heavily coiling the chromatin. Turns genes OFF (Heterochromatin).
Histone Acetylation: Adds acetyl groups to histone tails, loosening the DNA coil. Turns genes ON (Euchromatin).
Tags
EpigeneticsMethylationAcetylationHistones
In Eukaryotes, DNA is wrapped around proteins called Histones to form nucleosomes. The spacing of these histones dictates whether RNA Polymerase can access the gene (Transcription).
Chemical Modifications
Gene Expression Status
GENE IS OFF
Environmental Influence
Diet, stress, and toxins can alter methylation patterns. These acquired epigenetic changes can sometimes be passed down to offspring!