Available in PDF
 
In this issue...

In the News
Countering Bioterrorism
Genomes to Life Program
TIGR Anthrax Sequencing
Chromosome 20 Sequence
Pufferfish, Poplar Sequence
Microarrays, Anthrax ID
Patrinos Wins Award as Distinguished Executive
Spinach DNA: Hope for Blind
TIGR Functional Genomics
DOE Medical Technologies
Protein Trinity, Disorder
Gene p53 Research
PROSPECT Prediction
Low Dose Radiation Program
Award for Microscope
Bio-Science News at National Labs
Microbial Genome Program

Special Meeting Report
Genes and Justice
GM Products
Genetic Discrimination
What are GM Organisms and Foods?

Web, Publications, Resources
Biosciences Online
DNA Files on Radio
Primer on DNA Basics
CD-ROM Wins Rave Review
Other Resources

Funding Information
GTL Program Announcements
US Genome-Related Research Funding

Meeting Calendars & Acronyms
Genome and Biotechnology Meetings
Training Courses and Workshops
Acronyms

HGN archives and subscriptions
Human Genome Project Information home

Third Human Chromosome Finished

Chromosome 20 Genes Implicated in Diabetes, Obesity

Chromosome 20 is the first to be completely sequenced since publication of the working draft in February 2001. An effort of the Wellcome Trust Sanger Center (U.K.), this is the third and largest human chromosome finished to the high quality specified by the Human Genome Project. A paper reporting the work appeared in the December 20, 2001, issue of Nature. Some genes linked to chromosome 20 are implicated in Creutzfeldt-Jakob disease, severe combined immunodeficiency, Type 2 diabetes, obesity, cataract, and eczema. Other chromosomes completed thus far are 22 and 21, which were published in December 1999 and May 2000, respectively.

At almost 60 million bases, chromosome 20 comprises around 2% of the human genome. About 99.5% of its genetically active (euchromatic) regions were sequenced. Using analysis methods similar to those for the other chromosomes, researchers added such approaches as comparisons with newly released genomic sequences, including mouse and the pufferfish Tetraodon nigroviridis. These analyses can help reveal genes and regulatory elements having essential functions that have remained relatively unchanged by evolution. Authors report that some 727 genes were identified in the sequence.

Finishing the sequence of chromosome 20 (covering over 95% of the euchromatic portion with less then 1error in 10 kb) was a difficult task requiring a tedious “clone-by-clone” approach to find errors as small as single bases. Researchers suggest that some major discrepancies between the public human genome draft and finished data may be due to large duplicated regions of the genome. Completion of the remaining 21 human chromosomes is expected in 2003.

The electronic form of the newsletter may be cited in the following style:
Human Genome Program, U.S. Department of Energy, Human Genome News (v12n1-2).