Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study finds new gene mutations that lead to enlarged brain size, cancer, autism, epilepsy

02.07.2012
Researchers shed light on molecular cause of childhood’s worst conditions as first step toward developing more effective treatments

A research team led by Seattle Children's Research Institute has discovered new gene mutations associated with markedly enlarged brain size, or megalencephaly. Mutations in three genes, AKT3, PIK3R2 and PIK3CA, were also found to be associated with a constellation of disorders including cancer, hydrocephalus, epilepsy, autism, vascular anomalies and skin growth disorders.

The study, "De novo germline and postzygotic mutations in AKT3, PIK3R2 and PIK3CA cause a spectrum of related megalencephaly syndromes," was published online June 24 in Nature Genetics.

The discovery offers several important lessons and hope for the future in medicine. First, the research team discovered additional proof that the genetic make-up of a person is not completely determined at the moment of conception. Researchers previously recognized that genetic changes may occur after conception, but this was believed to be quite rare. Second, discovery of the genetic causes of these human diseases, including developmental disorders, may also lead directly to new possibilities for treatment.

AKT3, PIK3R2 and PIK3CA are present in all humans, but mutations in the genes are what lead to conditions including megalencephaly, cancer and other disorders. PIK3CA is a known cancer-related gene, and appears able to make cancer more aggressive. Scientists at Boston Children's Hospital recently published similar findings related to PIK3CA and a rare condition known as CLOVES syndrome in the American Journal of Human Genetics.

Physician researcher James Olson, MD, PhD, a pediatric cancer expert at Seattle Children's and Fred Hutchinson Cancer Research Center who was not affiliated with the study, acknowledged the two decades-worth of work that led to the findings. "This study represents ideal integration of clinical medicine and cutting-edge genomics," he said. "I hope and believe that the research will establish a foundation for successfully using drugs that were originally developed to treat cancer in a way that helps normalize intellectual and physical development of affected children. The team 'knocked it out of the park' by deep sequencing exceptionally rare familial cases and unrelated cases to identify the culprit pathway." The genes— AKT3, PIK3R2 and PIK3CA—all encode core components of the phosphatidylinositol-3-kinase (P13K)/AKT pathway, the "culprit pathway" referenced by Olson.

The research provides a first, critical step in solving the mystery behind chronic childhood conditions and diseases. At the bedside, children with these conditions could see new treatments in the next decade. "This is a huge finding that provides not only new insight for certain brain malformations, but also, and more importantly, provides clues for what to look for in less severe cases and in conditions that affect many children," said William Dobyns, MD, a geneticist at Seattle Children's Research Institute. "Kids with cancer, for example, do not have a brain malformation, but they may have subtle growth features that haven't yet been identified. Physicians and researchers can now take an additional look at these genes in the search for underlying causes and answers."

Researchers at Seattle Children's Research Institute will now delve more deeply into the findings, with an aim to uncover even more about the potential medical implications for children. "Based on what we've found, we believe that we can eventually reduce the burden of and need for surgery for kids with hydrocephalus and change the way we treat other conditions, including cancer, autism and epilepsy," said Jean-Baptiste Rivière, PhD, at Seattle Children's Research Institute. "This research truly helps advance the concept of personalized medicine."

Drs. Dobyns, Rivière and team made this discovery through exome sequencing, a strategy used to selectively sequence the coding regions of the genome as an inexpensive but effective alternative to whole genome sequencing. An exome is the most functionally relevant part of a genome, and is most likely to contribute to the phenotype, or observed traits and characteristics, of an organism.

Background On Researchers

Seattle Children's Research Institute conducted this study in collaboration with teams from University of Washington Genome Sciences Department, FORGE (Finding of Rare Disease Genes) Canada Consortium, Cedars Sinai Medical Center and University of Sussex.

Dr. Dobyns, who is also a UW professor of pediatrics, is a renowned researcher whose life-long work has been to try to identify the causes of children's developmental brain disorders such as megalencephaly. He discovered the first known chromosome abnormality associated with lissencephaly (Miller-Dieker syndrome) while still in training in child neurology at Texas Children's Hospital in 1983. That research led, 10 years later, to the discovery by Dobyns and others of the first lissencephaly gene known as LIS1.

Dr. Rivière is supported by a Banting Postdoctoral Fellowship from the Canadian Institutes of Health Research. As a lead researcher in the Dobyns lab, he also identified two new genes that cause Baraitser-Winter syndrome, a rare smooth brain malformation.

Co-authors on this study include: Jean-Baptiste Rivière, PhD, Banting Postdoctoral Fellow at Seattle Children's Research Institute; Judith St-Onge, Seattle Children's Research Institute; Christopher Sullivan, Seattle Children's Research Institute; Thomas Ward, Seattle Children's Research Institute; Ghayda Mirzaa, MD, University of Chicago; Brian O'Roak, PhD, University of Washington; Jay Shendure, MD, PhD, University of Washington; Mark O'Driscoll, PhD, University of Sussex; John Graham, MD, ScD, Cedars Sinai Medical Center; Kym Boycott, MD, PhD, University of Ottawa, Children's Hospital of Eastern Ontario; and many other physicians and scientists from North America and Europe.

Additional Resources

"De novo germline and postzygotic mutations in AKT3, PIK3R2 and PIK3CA cause a spectrum of related megalencephaly syndromes": http://www.nature.com/ng/journal/vaop/ncurrent/full/ng.2331.html

"Researchers find gene for 9-year-old girl's 1-in-a-million disease", CommonHealth/WBUR, May 2012: http://commonhealth.wbur.org/2012/05/life-of-riley-gene-cloves

"Cause of rare growth disease discovered", MedicalXpress, June 2012: http://medicalxpress.com/news/2012-06-rare-growth-disease.html

"Gene Mutations Cause Massive Brain Asymmetry", UC San Diego Health System, June 2012: http://health.ucsd.edu/news/releases/Pages/2012-25-hemimegalencephaly.aspx

About Seattle Children's Research Institute

At the forefront of pediatric medical research, Seattle Children's Research Institute is setting new standards in pediatric care and finding new cures for childhood diseases. Internationally recognized scientists and physicians at the Research Institute are advancing new discoveries in cancer, genetics, immunology, pathology, infectious disease, injury prevention and bioethics. With Seattle Children's Hospital and Seattle Children's Hospital Foundation, the Research Institute brings together the best minds in pediatric research to provide patients with the best care possible. Children's serves as the primary teaching, clinical and research site for the Department of Pediatrics at the University of Washington School of Medicine, which consistently ranks as one of the best pediatric departments in the country. For more information, visit http://www.seattlechildrens.org/research.

Mary Guiden | EurekAlert!
Further information:
http://www.seattlechildrens.org

More articles from Health and Medicine:

nachricht New study points the way to therapy for rare cancer that targets the young
22.11.2017 | Rockefeller University

nachricht Penn study identifies new malaria parasites in wild bonobos
21.11.2017 | University of Pennsylvania School of Medicine

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

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,...

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

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>