Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New type of genetic change identified in inherited cancer

06.10.2009
Duke University Medical Center and National Cancer Institute scientists have discovered that a novel genetic alteration – a second copy of an entire gene – is a cause of familial chordoma, an uncommon form of cancer arising in bones and frequently affecting the nervous system.

Inherited differences in gene copy number, known as copy number variation (CNV), have been implicated in some hereditary diseases but none of the previously discovered familial cancer genes has had CNV as the genetic change.

"This alteration is unlike anything we have ever seen before in families that tend to develop the same kind of cancers," says Michael Kelley, M.D., an associate professor at Duke University Medical Center and senior author of the study appearing in Nature Genetics. "We are not talking about a mutation in a single gene, but the duplication of an entire gene. This discovery is a classic example of where science answers one question but raises many, many more."

Chordoma is rare, striking only one in every million people. But it is a devastating diagnosis. People who have the disorder typically develop tumors at the base of the skull, in the pelvis, or along the spinal column. The growths are thought to arise from remnants of the notochord, an embryonic precursor to spinal column. There are few treatments and no cure for chordoma; most who have the disease usually die within 10 years.

Kelley, chief of hematology and oncology at the Durham Veterans Affairs Medical Center, has been studying chordoma for years after a collaborator at the National Cancer Institute, Dilys Parry, a co-author of the study, discovered a family with a history of the disease spanning several generations. They concluded that there had to be some sort of inherited genetic defect at work. Parry conducted clinical studies that eventually identified six additional families with multiple relatives with chordoma.

Initial work focused on possible defects on chromosome 7, but no defect was found that was shared by all of those affected. Researchers conducted linkage studies that revealed six new areas in the genome where potential mutations were likely. But it wasn't until they used a technique called array comparative genomic hybridization, a method that allowed them to see structural changes in the genome in exquisite detail, that they were able to pinpoint the source of the culprit. They identified it as the T (Brachyury) gene on chromosome 6.

"Brachyury is a transcription factor that helps regulate the development of the notochord and we know the gene is overly active in the tumor tissue in many people with chordoma," says Kelley, "so we were pretty sure we were on to something."

Investigators screened 65 individuals (21 with chordoma) in seven families with a history of the disease, specifically looking for any alterations in the T gene. They discovered that all the patients with chordoma in four of the seven families had a second copy of the T gene. The duplication did not appear among members of the three other families, nor did it appear in 100 healthy, normal controls.

Kelley says investigators do not understand what Brachyury does to cause chordoma. Brachyury expression was found in tissue from chordomas not only in patients who had inherited the duplication but also in those who did not have the duplication.

"It is likely that other genes are at work here, or that some other mechanism we do not yet understand is in play. Based on our research, however, we do feel that it may be worthwhile to screen for complex genomic rearragements when trying to find the cause of familial cancers. It may be a more productive route than traditional gene-mapping methods."

Xiaohong Yang of the National Cancer Institute wrote the first draft of the paper, and along with David Ng, also of the NCI, analyzed the data. Ng, Sufeng Li, Kelly and David Alcorta, all of Duke, performed the laboratory studies including genotyping, sequencing and breakpoint evaluation. Parry, Ng, Eamonn Sheridan of St. James Hospital in Leeds, UK, and Norbert Liebsch, from Massachusetts General Hospital, identified and evaluated the chordoma families. Yang, Ng, Kelley, Parry and Alisa Goldstein planned the work and interpreted the results.

The study was funded by the U.S. Department of Veterans Affairs, the National Cancer Institute and the Chordoma Foundation.

Michelle Gailiun | EurekAlert!
Further information:
http://www.duke.edu

More articles from Life Sciences:

nachricht Could this protein protect people against coronary artery disease?
17.11.2017 | University of North Carolina Health Care

nachricht Microbial resident enables beetles to feed on a leafy diet
17.11.2017 | Max-Planck-Institut für chemische Ökologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>