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.Hans Winkler, Professor of Botany at the University of Hamburg, Germany, as a combination of the words gene and chromosome. 

 An online copy is available here:  

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 ...." Winkler H. 1920. Verbreitung und Ursache der Parthenogenesis im Pflanzen- und Tierreiche. Fischer, Jena.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",Dobzhansky T. 1937. Genetics and the origin of species. Columbia N.Y. 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 
OrganismGenome size (base pairs)NoteVirus, Bacteriophage MS23569 First sequenced RNA-genome Virus, SV405224Virus, Phage Φ-X1745386First sequenced DNA-genomeVirus, Phage λ5×104Bacterium, Candidatus Carsonella ruddii1.6×105Smallest non-viral genome, Feb 2007Bacterium, Escherichia coli4×106Best-researched bacterium. Bacterium, Solibactoer usitatus1×107Largest known bacterial genomeProtist,  Amoeba dubia6.7×1011Largest known genome, but disputed.ScienceShot: biggest genome ever , comments: "The measurement for Amoeba dubia and other protozoa, which were reported to have very large genomes, were made in the 1960s using a rough biochemical approach which is now considered to be an unreliable method for accurate genome size determinations".Plant,  Arabidopsis thaliana1.57×108First plant genome sequenced, Dec 2000.Greilhuber J. et al. 2006. Smallest angiosperm genomes found in Lentibulariaceae, with chromosomes of bacterial size. Plant Biology. 8: 770-777.Plant,  Genlisea margaretae6.34×107Smallest recorded flowering plant genome, 2006.Plant,  Fritillaria assyrica1.3×1011Plant, Populus trichocarpa4.8×108First tree genome, Sept 2006Yeast, Saccharomyces cerevisiae2×107Fungus, Aspergillus nidulans3×107Nematode, Caenorhabditis elegans9.8×107First multicellular animal genome, December 1998.Insect, Drosophila melanogaster aka fruit fly1.3×108Insect, Bombyx mori aka silk moth5.30×108Insect, Apis mellifera aka honey bee1.77×109Fish, Tetraodon nigroviridis, type of Puffer fish3.85×108Smallest vertebrate genome knownMammal, Homo sapiens3×109Fish, Protopterus aethiopicus aka marbled lungfish1.3×1011Largest 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 

 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. 

 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.

Category:Genetics