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re:我也在Autism sperks网站上读...
我也在Autism sperks网站上读到了这篇文章，科学家们认为这是最新发现，真盼望他们能发现更多。把原文帖在这里，供大家研究．下个月我将去参加一个研讨会，可能有机会见到Autism Speaks的创办人，真希望能多了解一些他们的情况，斑竹有什么建议吗？
Global study of 1,200 families links new genes to autism
Ian Sample, science correspondent
Monday February 19, 2007
The Guardian
The world's largest search for genes linked to autism has uncovered new mutations believed to raise a child's risk of developing the brain disorder.
Scans of DNA from nearly 1,200 families with two or more children affected by autism have broadened the list of genes involved with the condition and will allow doctors to screen more young people for autism at an early age, when therapies are most effective.
Autism typically disrupts a person's ability to communicate and form social relationships, leading to serious behavioural problems. The five-year gene search is the first part of the Autism Genome Project, a collaboration of more than 120 scientists at 50 institutions around the world. Part of the study, published in Nature Genetics yesterday, involved checking for so-called copy number variations, in which there is either an extra or missing copy of a gene.
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The search found two new mutations - one in an unknown gene on chromosome 11, and the second a defect in a protein called neurexin 1, which works with a brain messenger chemical called glutamate to enable neighbouring neurons to communicate with one another.
Anthony Monaco, an autism genetics expert at Oxford University and leader of the UK part of the study, said 10% to 20% of cases could be down to additional or missing copies of crucial genes. Inheriting more mutated forms of key genes may lead to a more severe form of the condition.
Geraldine Dawson, a co-author at the University of Washington's Autism Centre, said: "As we identify these genes we will be able to screen young children for autism at an early age and begin interventions earlier, which can have a dramatic effect for some children."
Last year doctors at St Thomas' hospital in London revealed that autism and similar disorders were more common than suspected. They screened children aged nine and 10 and diagnosed autism or related disorders in more than 1%. Previously there were thought to be four to five cases per 10,000.
The researchers did not find that autism was becoming more common but believe it is now diagnosed more often. It affects nearly four times as many boys as girls.
The second phase of the project is due to begin this year when researchers focus on the genes identified and conduct a more intense search for other genetic factors.
The search has only been possible because of recent advances in biomedical technology, in particular gene chips, which allow fast testing of entire genomes, "There are going to be a lot more diseases that give up their culprits because of this technology," said Prof Monaco.
Autism Family Scan Identifies New Genetic Targets (Update2)
By Joi Preciphs and Reg Gale
Feb. 18 (Bloomberg) -- When Michael Giangregorio's sons grow up, their father wants to be able to tell them that the autism now affecting the younger of the two, 5-year-old Nicholas, won't be handed down to their children.
Doctors have long known autism runs in families. Now, scientists have scanned DNA from 1,168 families with multiple cases, the largest such group ever assembled, and identified gene variants that could one day spur treatments for a disorder that leaves about 1 in 150 U.S. children uncommunicative, cut off emotionally from the world around them.
The findings, announced today, include a deleted gene, called neurexin 1, that enables communication between neurons, the nerve cells in the brain that transmit information to the body through chemical and electrical signals. The researchers also found variants in two chromosomes that have never before been linked with the spectrum of similar disorders that includes autism and Asperger's Syndrome.
``This is the most ambitious effort yet to find the locations of genes that may confer vulnerability to autism, revealing clues that will likely influence the direction of autism research for years to come,'' said Elias Zerhouni, director of the U.S. National Institutes of Health in Bethesda, Maryland, in a statement today.
The NIH helped sponsor the work done by 120 scientists and 50 institutions in l9 countries who began work in 2002, a group known as the Autism Genome Project Consortium. Their findings will be published in the journal Nature Genetics.
The hope is that by mapping genetic flaws tied to the disorders, scientists will be able to better understand how they work and determine whether they can be fixed, said Bernie Devlin, associate professor of psychiatry and human genetics at the University of Pittsburgh, and an author of the study.
`A Ways Away'
``We'd like to think that eventually we'll be able to pinpoint individual genes that affect certain symptoms and treat them, sure'' Devlin said in a telephone interview yesterday. ``That's a ways away, of course, but it's something we're working toward.''
Devlin said a report earlier this month showing that manipulation of genes in mice ended symptoms of Rett Syndrome, a rare genetic disease related to autism, suggests they may be on the right track, even though the spectrum of autism disorders seen in humans offers a much tougher target.
``The finding we're announcing is just a first step,'' he said. ``We have funding to continue working, and I'd be surprised if we don't have another big announcement within a year. While we're looking at 10,000 SNPs now, we will be looking at 500,000 or a million going forward.'' SNPs, or single nucleotide polymorphisms, are the variations in DNA that make each individual unique.
Two Methods
The new findings combined two scientific methods, said Andy Shih, the chief science officer for Autism Speaks, a New York- based nonprofit advocacy group that also helped fund the study.
This included traditional inheritance studies and new technology that searches for changes in the ``architecture of chromosomes,'' the long strings of genetic and other material that make up the human genome, Shih said in a telephone interview yesterday.
The study pinpointed previously unknown links to the disorders on chromosomes 11 and 15, and long-suspected connections in other chromosomes known to carry so-called neurotransmitter genes. That included deletion of the neurexin 1 gene that's involved in communication between so-called glutamate neurons in the brain.
``That part wasn't a surprise,'' Shih said. ``It makes sense that genes might be implicated that effect cell-to-cell communication, given what we know about autism.''
The fact that a spectrum of similar disorders exists speaks to how complicated the genetic aspects may be, Shih said.
`Varied Deficits'
``Deficits can be quite varied from child to child, which means that genes in certain pathways might be affected in different ways,'' he said. In some cases, the deficits can lead to severe developmental disability. While other children can communicate at a higher level, they often don't socialize easily with others and exhibit learning disabilities.
``There might be different genetic combinations among families that affect the disorder in terms of the severity or nature of the deficits,'' Shih said. ``That means it could be a while before we sort out anything resembling a treatment.''
There are also environmental factors involved, he said, adding, ``It's really quite a puzzle.''
For Michael Giangregorio, it is a puzzle his family lives with every day.
Giangregorio, who resides in Merrick, New York, said his son Nicholas was diagnosed with autism at about 16 months. His son Michael, who is 7, doesn't have autism, he said.
When Nicholas was first diagnosed, health officials said that about 1 in 250 children had autism. This month, the U.S. Centers for Disease Control and Prevention in Atlanta released new figures acknowledging the prevalence has increased to 1 in 150. Giangregorio said there also a growing awareness about autism in the community at large.
`Awareness'
``It used to be you didn't know where to go, what to do, who to talk with,'' Giangregorio said in a telephone interview yesterday. ``Awareness has grown 100-fold. There's a national understanding that this is something we need to solve.''
That increased awareness is leading to a raft of new studies on the disorders, now largely treated with behavioral rather than biological therapies. While Michael has made progress with behavioral therapies, there is much work to be done in the future, Giangregorio said.
``Right now, the success of the biological treatments are largely anecdotal; we're not sure what's happened there yet,'' said Shih. ``There has been success with behavioral treatments, particularly when intervention is early.''
Giangregorio said he's looking forward to a day ``when my oldest comes to me and tells me he wants to get married. I'm hopeful that the work being done right now will enable me to tell him that everything is going to be all right. We've figured this thing out.''
To contact the reporter on this story: Joi Preciphs in Washington at jpreciphs1@bloomberg.net ; Reg Gale at rgale5@bloomberg.net
Last Updated: February 18, 2007 20:46 EST
Tiny Genetic Variations Raise Autism Risk
Main Category: Autism News
Article Date: 18 Feb 2007 - 13:00 PST
According to international research involving 19 countries, 120 scientists and 50 institutions, tiny variations in genes may increase the risk for autism spectrum disorders (ASD). The Autism Genome Project (AGP) Consortium's report can be seen in the journal Nature Genetics, February 18th issue.
The AGP's aim is to identify specific genes and variants that might raise vulnerability to autism. This includes looking into the how genes interact with other genes, as well as other factors, such as the environment. The scientists are also looking into how potential susceptibility genes may work in the brain to bring about ASD.
NIH Director Elias A. Zerhouni, M.D., said "This is the most ambitious effort yet to find the locations of genes that may confer vulnerability to autism. The AGP is revealing clues that will likely influence the direction of autism research for years to come."
Dr. Bernie Devlin, University of Pittsburgh Medical School , one of the corresponding authors on the project, said "Although we know autism is highly heritable, complex gene interactions and submicroscopic anomalies create a din of statistical noise that drowns out detection of signals from linked sites in the genome. To amplify these signals, we brought to bear gene chip technology with a huge sample, and also screened for these fine-level anomalies, factoring them into the analysis."
The scientists say there are now clues that implicate components of the brain's glutamate neurotransmitter system in ASD. Glutamate is crucial in wiring up the brain early on in its development - glutamate enhances neuronal activity. Some genes that are associated with the glutamate system are located in chromosome regions that are linked to ASD, say the scientists.
New evidence has also emerged linking autism and gene sites for neurexins. Neurexins are molecules that construct glutamate synapses - through which brain cells communicate.
A site on chromosome 11 most strongly linked to autism in this study harbors genes for proteins that shuttle glutamate across the synapse. Although detected previously, the linkage signal at this site was regarded as less important until now.
Submicroscopic anomalies - tiny deletions, or the doubling, tripling or even multiplying of stretches of genetic material - are relatively common in the human genome and aren't necessarily harmful. However, recent evidence suggests that these anomalies may contribute to risk for - or rarely even cause - autism if they affect certain sites associated with the disorder. The AGP researchers found a number of these variations in such suspect chromosomal locations in affected individuals, including deletion of a neurexin gene.
please look into this website also:
http://www.autismspeaks.org/press/agp_results.php
The following event took place at the National Prayer Breakfast where Dr. Collins gave a speech. The comments are written by a non-Christian reporter 鈥?.The oddball highlight of the morning, though, was offered by Dr. Francis Collins, director of the Human Genome Project, believer in Christ and world-famous geneticist. In his keynote speech, Collins gave a passionate defense of the intertwining of faith and science, insisting that one point of view does not automatically negate the other. Then, as punctuation, the scientist pulled out an acoustic guitar, and like a wacky nursery school teacher, sang a hymn that glorified human wisdom and knowledge.
No one but a geek, as he called himself, could have pulled off such a stunt without drawing the derision of the crowd. But Collins is a geek and soon all 3,400 guests 鈥?from the Ukraine, Senegal, Belize, Texas, Virginia, and Brooklyn 鈥? were singing along. In that moment I saw what I wish the people trapped on both sides of the culture wars could see: That there is a time and place for talking about God in an earnest, personal, heartfelt way; that such talk is not, in itself, threatening or loaded; and that, if done honestly, with intelligence, humor and humility, can inspire people to feel the miracle鈥攁nd the responsibilities
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发表于 2007-3-19 19:45:47
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发表于 2007-3-19 20:05:19