Featured Research

from universities, journals, and other organizations

Mutant Mouse Provides Insights Into Breast Cancer

Date:
December 13, 2006
Source:
Cornell University
Summary:
By discovering a mutant mouse that is highly susceptible to mammary tumors, Cornell researchers have found a novel potential link between genetic defects in DNA replication and breast cancer.

This image shows chromosomes from a Chaos3 mouse with mutant Mcm4 genes. The arrows point to chromosomes with breaks or aberrations resulting from flawed DNA replication.
Credit: Image provided by John Schimenti

By discovering a mutant mouse that is highly susceptible to mammary tumors, Cornell researchers have found a novel potential link between genetic defects in DNA replication (copying) and breast cancer.

The mouse contains a mutation in a gene essential for replicating DNA in both humans and mice that increases the rate of flawed copies of genetic material, leading to mouse breast cancers.

In a paper published in Nature Genetics online (and upcoming in the Dec. 27 print issue), the Cornell geneticists report that by extensively testing hundreds of mice pedigrees, they found a mutant line of mice called Chaos3 that had a 20-fold increase in a hallmark for cancer called genomic instability -- a blanket term for an elevation in the number of mutations, chromosomal aberrations or loss of integrity of genetic information that occur when DNA replicates. While the Chaos3 mice appear normal in every way, the females are highly predisposed to mammary tumors.

"It's known that most cancers, by the time you look at them, have genomic instability in some form or another," said John Schimenti, a genetics professor in Cornell's Departments of Biomedical Sciences, and Molecular Biology and Genetics and the paper's senior author. "Our research demonstrated that genomic instability is probably leading to these cancers."

Schimenti and colleagues found that in the Chaos3 mice, the DNA codings in a gene called Mcm4 were partially impaired. The Mcm4 gene is one of six related Mcm genes that play essential roles in replication and were originally discovered at Cornell in baker's yeast (S. cerevisiae). The genes have remained largely unchanged throughout evolution and are evident in archaebacteria, yeast, mammals and more. It is unknown why the impaired Mcm4 genes in the Chaos3 mice led exclusively to breast cancer, Schimenti said.

Mcm4 is essential for DNA replication and thus cell growth, according to Schimenti. Partially impaired Mcm4 genes, however, allow Chaos3 mice to live normal lives but greatly increase the rate of faulty DNA replications and genomic instability.

"It's insidious because there is no warning that one might have this cancer predisposing allele [DNA codings at a given site] because the mice live normally," said Schimenti, who is also director of the Center for Vertebrate Genomics.

The researchers plan to study further the other Mcm genes to see if they, too, play a role in cancers.

The Mcm genes were discovered by Cornell professor of molecular biology Bik Tye, while studies of the mouse tumors were done by Ana Alcaraz, a veterinarian in Cornell's Section of Anatomic Pathology in the Department of Biomedical Sciences.

The study was funded by the National Institutes of Health and a Department of Defense grant to lead author Naoko Shima, an assistant professor at the University of Minnesota's Department of Genetics, Cell Biology and Development.


Story Source:

The above story is based on materials provided by Cornell University. Note: Materials may be edited for content and length.


Cite This Page:

Cornell University. "Mutant Mouse Provides Insights Into Breast Cancer." ScienceDaily. ScienceDaily, 13 December 2006. <www.sciencedaily.com/releases/2006/12/061211124308.htm>.
Cornell University. (2006, December 13). Mutant Mouse Provides Insights Into Breast Cancer. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2006/12/061211124308.htm
Cornell University. "Mutant Mouse Provides Insights Into Breast Cancer." ScienceDaily. www.sciencedaily.com/releases/2006/12/061211124308.htm (accessed September 30, 2014).

Share This



More Plants & Animals News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
Argentina Worries Over Decline of Soybean Prices

Argentina Worries Over Decline of Soybean Prices

AFP (Sep. 27, 2014) The drop in price of soy on the international market is a cause for concern in Argentina, as soybean exports are a major source of income for Latin America's third largest economy. Duration: 01:10 Video provided by AFP
Powered by NewsLook.com
Mama Bear, Cubs Hang out in California Backyard

Mama Bear, Cubs Hang out in California Backyard

Reuters - US Online Video (Sep. 27, 2014) A mama bear and her two cubs climb trees, wrestle and take naps in the backyard of a Monrovia, California home. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com
'Crazy' Climate Forces Colombian Farmers to Adapt

'Crazy' Climate Forces Colombian Farmers to Adapt

AFP (Sep. 26, 2014) Once upon a time, farming was a blissfully low-tech business on Colombia's northern plains. Duration: 02:05 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins