Extrachromosomal DNA: Difference between revisions
CSV import |
CSV import |
||
| Line 36: | Line 36: | ||
{{stub}} | {{stub}} | ||
<gallery> | |||
File:PBR322_plasmid_showing_restriction_sites_and_resistance_genes.jpg|PBR322 plasmid showing restriction sites and resistance genes | |||
File:Map_of_the_human_mitochondrial_genome.svg|Map of the human mitochondrial genome | |||
File:Mitochondrial_inheritance.svg|Mitochondrial inheritance | |||
</gallery> | |||
Latest revision as of 04:16, 18 February 2025
Extrachromosomal DNA is a type of DNA that is not located within the chromosomes. Instead, it is found outside of the chromosomes in the cytoplasm or nucleus. This DNA can be found in various forms such as plasmids, mitochondrial DNA, and chloroplast DNA.
Overview[edit]
Extrachromosomal DNA is a significant part of the genetic material in a cell. It is not bound by the same restrictions as chromosomal DNA, allowing it to replicate independently and often at a faster rate. This can lead to an increase in the number of copies of certain genes, which can have various effects on the organism.
Types of Extrachromosomal DNA[edit]
Plasmids[edit]
Plasmids are small, circular pieces of DNA that are found in bacteria and some eukaryotes. They can replicate independently of the chromosomal DNA and can be transferred between cells. Plasmids often carry genes that provide a survival advantage to the organism, such as antibiotic resistance genes.
Mitochondrial DNA[edit]
Mitochondrial DNA (mtDNA) is found in the mitochondria, the energy-producing organelles in the cell. Unlike chromosomal DNA, mtDNA is inherited solely from the mother. Mutations in mtDNA can lead to various diseases, including Leber's hereditary optic neuropathy and mitochondrial myopathy.
Chloroplast DNA[edit]
Chloroplast DNA (cpDNA) is found in the chloroplasts of plants and algae. Like mtDNA, cpDNA is inherited from the mother. It is responsible for photosynthesis and other functions of the chloroplast.
Role in Disease[edit]
Extrachromosomal DNA can play a role in disease. For example, certain cancers have been found to have high levels of extrachromosomal DNA, which can lead to an increase in the number of copies of oncogenes. This can drive the growth and spread of the cancer.
