- News Home
17 April 2014 12:48 pm ,
Vol. 344 ,
Officials last week revealed that the U.S. contribution to ITER could cost $3.9 billion by 2034—roughly four times the...
An experimental hepatitis B drug that looked safe in animal trials tragically killed five of 15 patients in 1993. Now,...
Using the two high-quality genomes that exist for Neandertals and Denisovans, researchers find clues to gene activity...
A new report from the Intergovernmental Panel on Climate Change (IPCC) concludes that humanity has done little to slow...
Astronomers have discovered an Earth-sized planet in the habitable zone of a red dwarf—a star cooler than the sun—500...
Three years ago, Jennifer Francis of Rutgers University proposed that a warming Arctic was altering the behavior of the...
- 17 April 2014 12:48 pm , Vol. 344 , #6181
- About Us
Moms Spice Up Chromosome Swapping
11 June 2002 (All day)
When it comes to genome mapping, the spotlight has largely been on "physical" maps: those that list the millions of DNA bases embedded in an organism's genome. But many biologists also believe that genetic maps, which mark spots where DNA differs from one person to another, will prove critical in finding gene mutations linked to disease. Now a genetic map crafted by deCODE genetics, a company based in Reykjavik, Iceland, reveals surprising variations in how DNA passes from mothers to their children.
Until now, the largest genetic map for humans was created by the Marshfield Medical Research Foundation in Marshfield, Wisconsin. That map was constructed before the human genome was sequenced, which made it hard to place genetic markers in the right order. The deCODE scientists, in contrast, had the benefit of evolving drafts from the human genome sequence.
To assemble the map, the researchers, led by the company's CEO Kari Stefansson, collected samples from 869 people from 146 families in Iceland. Whenever possible, they included samples from both parents and their children, tracing how various pieces of chromosomes recombined upon fertilization to produce the offspring's new chromosomes. Stefansson's team identified 5136 spots on the genome where changes occurred. Scientists already knew that recombination shuffles the contents of maternal chromosomes 60% more than the contents of paternal chromosomes. Surprisingly, the team also found that some mothers' chromosomes get mixed up in their offspring more than those of other mothers'. Such differences in recombination may help explain why their families differ in disease susceptibility, says Stefansson.
The deCODE map "is about a fivefold improvement" in the resolution of the Marshfield map, says James Weber, director of the Center for Medical Genetics at Marshfield. "They've confirmed recent findings that individual women differ from each other," he adds. However, why that is "we can only speculate at this point." DeCODE published the map online 10 June in Nature Genetics and will make it freely available on its Web site.