University researchers and their colleagues in the International Human Genome Sequencing Project have published their scientific description of the finished human genome — reducing the estimated number of genes from 35,000 to only 20,000-25,000, a surprisingly low number for our species.
The paper appeared in the Oct. 21 issue of Nature.
“Not very long ago, we thought a reasonable estimate for the total number of human genes might be about 100,000,” said Richard K. Wilson, Ph.D., director of the Genome Sequencing Center (GSC). “Our first analysis of the working draft of the genome three years ago lowered that estimate to 30,000 to 35,000 genes, and now our clearest look yet has brought the estimate even lower.”
GSC scientists were significant contributors to the finished product, helping determine the identity of an estimated 30 percent to 40 percent of the 3 billion base pairs that make up human DNA.
The GSC has been a leader in developing innovative methods for sequencing DNA. Researchers have helped expedite, automate and conduct efforts to sequence human DNA and the DNA of several other species, including the mouse, chicken and chimpanzee; microscopic organisms like the roundworm C. elegans; and plants such as the weed Arabidopsis thaliana and moss.
To rapidly and effectively harness human genome information and other basic research for the improvement of patient treatment and diagnosis, in 2003 the University launched a new initiative known as BioMed 21. The effort promotes general interdisciplinary collaboration and puts a special emphasis on collaborations that leverage information and expertise available at the GSC.
The National Human Genome Research Institute and the U.S. Department of Energy (DOE) led the international consortium of researchers that produced the final human genome map.
The new paper proves that the finished genome sequence has both the high coverage and the accuracy needed to perform sensitive analyses, such as those focusing on the number of genes, segmental duplications involved in disease and the birth and death of genes over the course of evolution.
More than 2,800 researchers who took part in the International Human Genome Sequencing Consortium share authorship on the Nature paper, which expands upon the group’s initial analysis published in February 2001.
Even more detailed annotations and analyses have already been published for chromosomes 5, 6, 7, 9, 10, 13, 14, 19, 20, 21, 22 and Y. Publications describing the remaining 12 chromosomes are forthcoming.
The International Human Genome Sequencing Consortium includes scientists at 20 institutions in France, Germany, Japan, China, Great Britain and the United States.
The five largest sequencing centers are located at: Baylor College of Medicine; the Broad Institute of Massachusetts Institute of Technology and Harvard University; the DOE’s Joint Genome Institute; Washington University School of Medicine; and the Wellcome Trust Sanger Institute.