Genome

The **genome** of an organism is the whole of its hereditary information encoded in its DNA (or, for some viruses, RNA). This includes both the genes and the non-coding sequences of the DNA.
Professor Hans Winkler coined the term in 1920.

Winkler's definition, in translation, runs:
- "I propose the expression ***genome*** for the haploid chromosome set, which, together with the pertinent protoplasm, specifies the material foundations of the species ...." <sup>p165</sup>

However, no single haploid chromosome set defines even the DNA of a species. Because of the huge variety of alleles carried by a population, every individual is genetically different. Even a diploid individual carries genetic variety. For that reason Dobzhansky preferred "set of chromosomes", and the definition now must be broader than Winklers' definition. The genome of a haploid chromosome set is merely a _sample_ of the total genetic variety of a species.

The term 'genome' can be applied specifically to mean the complete set of nuclear DNA (the 'nuclear genome') but can also be used of organelles that contain their own DNA, as with the mitochondrial genome or the chloroplast genome.

## Genome sizes

|Organism|Genome size (base pairs)|Note|
| --- | --- | --- |
|Virus, Bacteriophage MS2|3569|First sequenced RNA-genome|
|Virus, SV40|5224||
|Virus, Phage Φ-X174|5386|First sequenced DNA-genome|
|Virus, Phage λ|5×10<sup>4</sup>||
|Bacterium, _Candidatus_ Carsonella ruddii|1.6×10<sup>5</sup>|Smallest non-viral genome, Feb 2007|
|Bacterium, _Escherichia coli_|4×10<sup>6</sup>|Best-researched bacterium.|
|Bacterium, _Solibactoer usitatus_|1×10<sup>7</sup>|Largest known bacterial genome|
|Protist,  _Amoeba dubia_|6.7×10<sup>11</sup>|Largest known genome, but disputed.|
|Plant,  _Arabidopsis thaliana_|1.57×10<sup>8</sup>|First plant genome sequenced, Dec 2000.|
|Plant,  _Genlisea margaretae_|6.34×10<sup>7</sup>|Smallest recorded flowering plant genome, 2006.|
|Plant,  _Fritillaria assyrica_|1.3×10<sup>11</sup>||
|Plant, _Populus trichocarpa_|4.8×10<sup>8</sup>|First tree genome, Sept 2006|
|Yeast, _Saccharomyces cerevisiae_|2×10<sup>7</sup>||
|Fungus, _Aspergillus nidulans_|3×10<sup>7</sup>||
|Nematode, _Caenorhabditis elegans_|9.8×10<sup>7</sup>|First multicellular animal genome, December 1998.|
|Insect, _Drosophila melanogaster_ aka fruit fly|1.3×10<sup>8</sup>||
|Insect, _Bombyx mori_ aka silk moth|5.30×10<sup>8</sup>||
|Insect, _Apis mellifera_ aka honey bee|1.77×10<sup>9</sup>||
|Fish, _Tetraodon nigroviridis_, type of Puffer fish|3.85×10<sup>8</sup>|Smallest vertebrate genome known|
|Mammal, _Homo sapiens_|3×10<sup>9</sup>||
|Fish, _Protopterus aethiopicus_ aka marbled lungfish|1.3×10<sup>11</sup>|Largest vertebrate genome known|

_Note:_ The DNA from a single human cell has a length of ~1.8 m (but at a width of ~2.4 nanometers).

## Related pages

- Bioinformatics
- Gene
- Sequence analysis
- Human genome
- ENCODE: the complete analysis of the human genome

## References

<div class="references-small">

- Benfey P. and Protopapas A.D. 2004. _Essentials of genomics_. Prentice Hall.
- Brown T.A. 2002. _Genomes 2_. Bios Scientific Publishers.
- Gibson G. and Muse S.V. 2004. _A primer of genome science_. 2nd ed. Sinauer Assoc.
- Gregory T.R. (ed) 2005. _The evolution of the genome_. Elsevier.
- Reece R.J. 2004. _Analysis of genes and genomes_. Wiley.
- Saccone C. and Pesole G. 2003. _Handbook of comparative genomics_. Wiley.
- Werner E. 2003. In silico multicellular systems biology and minimal genomes. _Drug Discov Today_. **8**(24):1121-7. PubMed
- Witzany G. 2007. Natural genome editing competences of viruses. _Acta Biotheoretica_. https://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&TermToSearch=17347785&ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum
</div>

## Other websites

- DNA Interactive: the history of DNA science
- DNA from the beginning
- All about the human genome project from Genome.gov
- Animal genome size database
- Plant genome size database
- GOLD:Genomes OnLine Database
- The Genome News Network
- NCBI Entrez Genome Project database
- NCBI Genome Primer
- BBC News - Final genome 'chapter' published
- Software that maps an Artificial Genome sequence to a Network and to a Lineage tree
- IMG The integrated microbial genomes system, for genome analysis by the DOE-JGI.