Genome

For other uses, see Genome (disambiguation).

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.^[1]

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 ...." ^[2]p165

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",^[3] 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[4]
Virus, SV40	5224[5]
Virus, Phage Φ-X174	5386	First sequenced DNA-genome[6]
Virus, Phage λ	5×104
Bacterium, Candidatus Carsonella ruddii	1.6×105	Smallest non-viral genome, Feb 2007
Bacterium, Escherichia coli	4×106	Best-researched bacterium.[7]
Bacterium, Solibactoer usitatus	1×107	Largest known bacterial genome
Protist, Amoeba dubia	6.7×1011	Largest known genome, but disputed.[8]
Plant, Arabidopsis thaliana	1.57×108	First plant genome sequenced, Dec 2000.[9]
Plant, Genlisea margaretae	6.34×107	Smallest recorded flowering plant genome, 2006.[9]
Plant, Fritillaria assyrica	1.3×1011
Plant, Populus trichocarpa	4.8×108	First tree genome, Sept 2006
Yeast, Saccharomyces cerevisiae	2×107
Fungus, Aspergillus nidulans	3×107
Nematode, Caenorhabditis elegans	9.8×107	First multicellular animal genome, December 1998.[10]
Insect, Drosophila melanogaster aka fruit fly	1.3×108
Insect, Bombyx mori aka silk moth	5.30×108
Insect, Apis mellifera aka honey bee	1.77×109
Fish, Tetraodon nigroviridis, type of Puffer fish	3.85×108	Smallest vertebrate genome known
Mammal, Homo sapiens	3×109
Fish, Protopterus aethiopicus aka marbled lungfish	1.3×1011	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