San Diego, June 16, 2003 -- Researchers from the University of California, San Diego (UCSD) Jacobs School of Engineering have uncovered evidence that major evolutionary changes are more likely to occur in approximately 400 'fragile' genomic regions that account for only 5 percent of the human genome. The findings, reported in the June 24 issue of the Proceedings of the National Academy of Sciences (PNAS), undercut the widely held view among scientists that evolutionary breakpoints -- disruptions in the order of genes on chromosomes -- are purely random. Apart from its implications for evolutionary theory, the study could have major implications for medical research related to diseases such as leukemia, which are caused by clinical (rather than evolutionary) chromosomal breakpoints.

"These rearrangements are like earthquakes that are more likely to happen along fault lines, which is why you're more likely to see a quake in Los Angeles than Chicago," said Pavel Pevzner, the Ronald R. Taylor Chair in the Jacobs School's Computer Science and Engineering department, who co-authored the study with project scientist Glenn Tesler. "Similarly, there are 'faults' within the human genome. They are fragile regions, as opposed to solid regions that show much less propensity for rearrangement and make up about 95 percent of the genome."

Pevzner and Tesler are experts in bioinformatics -- the use of computing and mathematics to study genomes -- and their study grew out of the first giant genomic sequencing projects, funded in part by the National Institutes of Health. Those projects resulted in DNA sequencing of the human and mouse genomes. In December 2002, that comparison led the scientists to compute 281 large blocks (of one million 'letters' or more, out of roughly three billion letters in the mammalian genome), and 245 major rearrangements since the two species evolved from a common ancestor 75 million years ago. "Like the ancient super-continent Pangea broke
'"/>

Contact: Doug Ramsey
dramsey@ucsd.edu
858-822-5825
University of California - San Diego
16-Jun-2003

Page: 1 2 3
Related biology news :

1. Scientists sequence genome of kind of organism central to biospheres carbon cycle
2. Keep genome data freely accessible
3. The book opens on the first tree genome
4. NSF awards 22 new projects for plant genome research
5. Milk genome symposium
6. Environmental decontamination, greenhouse gases, and the genome of a methane-loving bacterium
7. Scientists explore genome of methane-breathing microbe
8. National Academies advisory: genome data and bioterrorism
9. Adaptive changes in the genome may provide insight into the genetics of complex disease
10. Complex cells likely arose from combination of bacterial and extreme-microbe genomes
11. Researchers identify the genomes controlling elements