The epigenetic code is hypothesised to be a defining code in every

eukaryotic Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacte ...

cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery ...

consisting of the specific

epigenetic In biology, epigenetics is the study of stable phenotypic changes (known as ''marks'') that do not involve alterations in the DNA sequence. The Greek prefix '' epi-'' ( "over, outside of, around") in ''epigenetics'' implies features that are "o ...

modification in each cell. It consists of histone modifications defined by the

histone code The histone code is a hypothesis that the transcription of genetic information encoded in DNA is in part regulated by chemical modifications (known as ''histone marks'') to histone proteins, primarily on their unstructured ends. Together with sim ...

and additional epigenetic modifications such as

DNA methylation DNA methylation is a biological process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts t ...

. The base for the epigenetic code is a system above the

genetic code The genetic code is the set of rules used by living cells to translate information encoded within genetic material ( DNA or RNA sequences of nucleotide triplets, or codons) into proteins. Translation is accomplished by the ribosome, which links ...

of a single cell. While in one individual the genetic code in each cell is the same, the epigenetic code is tissue and cell specific. The epigenetic code can be multidimensional in nature. It could include any of the three major cellular macromolecucles; namely, DNA (code independent), RNA, and/or protein. In some ciliates potential structural codes have also been suggested.

References

{{more citations needed, date=January 2007 Epigenetics

See also

References