Comparative genomics

http://www.ornl.gov/sci/techresources/Human_Genome/faq/compgen.shtml

What are the comparative genome sizes of humans and other organisms being studied? organism estimated size(base pairs) estimated  gene number average gene density chromosome number Homo sapiens (human) 3.2 billion ~25,000 1 gene per 100,000 bases 46 Mus musculus  (mouse) 2.6 billion ~25,000 1 gene per 100,000 bases 40 Drosophila melanogaster (fruit fly) 137 million 13,000 1 gene per 9,000 bases 8 Arabidopsis thaliana (plant) 100 million 25,000 1 gene per 4000 bases 10 Caenorhabditis elegans (roundworm) 97 million 19,000 1 gene per 5000 bases 12 Saccharomyces cerevisiae (yeast) 12.1 million 6000 1 gene per 2000 bases 32 Escherichia coli (bacteria) 4.6 million 3200 1 gene per 1400 bases 1 H. influenzae  (bacteria) 1.8 million 1700 1 gene per 1000 bases 1 *Information extracted from genome publication papers below. http://www.nature.com/nature/journal/v420/n6915/full/nature01262.html Initial sequencing and comparative analysis of the mouse genome Nature 420, 520-562 (5 December 2002) | doi:10.1038/nature01262; Received 18 September 2002; Accepted 31 October 2002
The proportion of mouse genes with a single identifiable orthologue in the human genome seems to be approximately 80%. The proportion of mouse genes without any homologue currently detectable in the human genome (and vice versa) seems to be less than 1%.
Dozens of local gene family expansions have occurred in the mouse lineage. Most of these seem to involve genes related to reproduction, immunity and olfaction, suggesting that these physiological systems have been the focus of extensive lineage-specific innovation in rodents.

Indeed, below we show that about 40% of the human genome can be aligned confidently with the mouse genome.

In total, about 90.2% of the human genome and 93.3% of the mouse genome unambiguously reside within conserved syntenic segments.