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Genomics

Genomics is the study of an organism's genome and the use of the genes. It deals with the systematic use of genome information, associated with other data, to provide answers in biology, medicine, and industry.

Genomics appeared in the 1980s and took off in the 1990s with the initiation of genome projects for several species.

The related field of genetics is the study of genes and their role in inheritance.

Genomics has the potential of offering new therapeutic methods for the treatment of some diseases, as well as new diagnostic methods. Other applications are in the food and agriculture sectors.

The major tools and methods related to genomics are bioinformatics, genetic analysis, measurement of gene expression, and determination of gene function.

Comparison of genomes has resulted in some surprising biological discoveries. If a particular DNA sequence is present among many members of a clade, that sequence is said to have been conserved among the species, implying that it confers a selective advantage to the organisms. Experimental investigation of these sequences (revealed by genomic sequencing) has shown that some are transcribed into small RNA molecules, although the functions of these RNAs were not immediately apparent.

The identification of similar sequences (including many genes) in two distantly related organisms, but not in other members of one of the clades, has led to the theory that these sequences were acquired by horizontal gene transfer. This phenomenon is most prominent in thermophilic bacteria, where it seems that genes were transferred from Archaea to Eubacteria. It has also been noticed that bacterial genes exist in eukaryotic nuclear genomes and that these genes generally encode mitochondrial and plastid proteins, giving support to the endosymbiotic theory of the origin of these organelles.

The first genome to be sequenced was that of Haemophilus influenzae[?] in 1995, and more genomes are being sequenced at an increasing pace. A rough draft of the human genome was completed by the Human Genome Project in early 2001 amid much fanfare.

Genetic similarity

It is often stated that such-and-such an organism shares X percent of its DNA with humans. Here is a list of genetic similarity[?] to humans, with sources, where known.

Perhaps a geneticist (or should that be genomicist?) would care to comment on the significance, if any, of these statistics.

 Human         99.9% (quoted by President Clinton, Jan 2000, State of the Union address;
                      also Human Genome Project)
               100%    (identical twins)
 Chimpanzee    98.4% (sources: Americans for Medical Progress; 
                               Jon Entine in the San Francisco Examiner)
               98.7% (Richard Mural of Celera, quoted on MSNBC)
 Mouse         98%   (source: Americans for Medical Progress)
 Gorilla       97%   (Queer Jihad web site)
 Dog           95%   (Jon Entine in the San Francisco Examiner)
 Roundworm     74%   (Jon Entine in the San Francisco Examiner)
 Banana        50%   (source: Americans for Medical Progress)

See also

gene therapy -- genetic engineering

Sources and external links



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