8th August,2002; 15:49:54 -0400
By Amy Norton
By comparing the two completed maps of the human genome, researchers have identified more than 100 chunks of DNA that could be associated with a range of diseases.
These potential "hot spots" in the human genetic makeup are called segmental duplications--a chromosome segment that exists in more than one copy in the genome. Genes within these repeated segments can be overexpressed, and a number of human genetic disorders are already known to be associated with such increased gene expression.
To uncover segmental duplications within the human genome, researchers led by Evan E. Eichler of Case Western Reserve University in Cleveland, Ohio, combined data from the publicly funded Human Genome Project and the private genome-mapping effort by Celera Genomics.
They report their findings in the August 9th issue of Science.
Eichler told Reuters Health that his team was able to "ferret out" 145 new DNA regions that are flanked by nearly identical duplications. Twenty-four other "hot spots" they identified have already been tied to genetic disease.
Because these 145 new sites are potential areas of what scientists call "genetic instability," they should now be studied for their role in human disease, according to Eichler.
"In the future," he said, "we can focus on these regions to determine if they associate with uncharacterized human diseases"--such as autism and mental retardation with no apparent cause.
SOURCE: Science 2002;297:1003-1007.
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