Author:
USA Today 12/01/2004
[ Edit | View ]
|
Date Posted: 18:50:11 01/21/04 Wed
(170-215-170-197.bras01.cha.wv.frontiernet.net/170.215.170.197)
USA Today 12/01/2004
By Kim Painter
When Blake Draut was 2˝ years old, a specialist told his parents that their son's speech delays and odd habits, his fears of dirty hands and grassy feet, were part of a bigger problem: autism. When the specialist learned that Blake was part of a set of fraternal triplets, all with developmental quirks, "she wanted to see all three," recalls Blake's mother, Danielle Draut.
Several months and several evaluations later, the Anaheim, Calif., family had the news: Two of the three boys were autistic. The third, who turned out to have a hearing problem, didn't qualify for an autism diagnosis but did show some of the rigid behaviors associated with the disorder.
What might sound like an extraordinary run of bad luck was actually nothing of the sort: Scientists have known for some time that autism often runs in families. Studies suggest that if one child is autistic, there's a 5% to 10% chance that any sibling will be autistic, and a 30% to 40% chance that the sibling will have milder, but related, problems. If the sibling is an identical twin, the risk for autism shoots to between 60% and 90%, says Andy Shih, research director of the National Alliance for Autism Research.
Although environmental factors clearly play a role, "autism is the most genetic of neuropsychiatric syndromes," more strongly linked to genes than schizophrenia or bipolar disorder, says Dan Geschwind, a genetics researcher at the University of California-Los Angeles.
And now researchers are poised to learn which genes are involved in autism, how they work and how their effects might be blunted. It's all part of a new push for autism answers, fueled by new technology, new funding and, perhaps most important, a heightened public awareness of an increasingly diagnosed disorder.
"It's a very exciting time," Geschwind says.
Geschwind was among autism researchers who spoke recently at a summit in Washington, D.C., sponsored by the federal government. At the meeting, government officials laid out a 10-year plan for improving services for autistic people and for studying its causes and possible treatments.
High on the list of priorities is finding the genes associated with autism. At the meeting, the private autism research alliance and the public National Institutes of Health announced a partnership to do just that. The NIH is contributing $2.5 million, and the alliance is contributing $2 million to start the project, which will help to link the work of 170 researchers around the world, Shih says.
Actually running it over the next five years will cost up to $25 million, money that has not yet been committed, Shih says.
And finding the genes will be a complex task.
Preliminary research suggests that 15 to 20 different genes may contribute to autism susceptibility — and that different combinations of those genes may cause different variations in different people.
"In child A, it may be genes number 2, 4 and 6; child B may have 1, 3 and 6 interacting," Shih says. "Ideally, this project should be able to identify all of the possible combinations."
Finding so many genes in so many combinations will require many DNA samples from affected families, experts say. "The power is in the numbers," says Thomas Insel, director of the National Institute of Mental Health (NIMH).
Genetic resource exchange
That's where families like the Drauts come in. About a month ago, Danielle, her husband, Jon, and the boys got a visit from a medical technician who took several tubes of blood from each family member. Sometime soon, specialists will visit the family home to observe the boys, who are now almost 5, and take detailed histories of their development.
They also will interview Danielle and Jon about their family histories, looking not only for a history of autism, but also for a history of related disorders and traits — everything from language delays to obsessive-compulsive disorder.
The project in which the family is participating is called the Autism Genetic Resource Exchange. It started in the late 1990s as a private effort financed by the Cure Autism Now Foundation. At that time, the Los Angeles advocacy group was begging scientists to do more research on autism genes and was finding that a major obstacle was a lack of genetic samples, says foundation founder Jon Shestack. "There wasn't much of it, and most of it was in the hands of scientists who didn't necessarily want to share," says Shestack, himself the father of an autistic boy.
Over five years, the project collected blood samples and histories from 450 families with multiple cases of autism or other disorders on the so-called autism spectrum. The blood has been turned into renewable cell lines, available for research for a small fee. A few months ago, the project got a $3.9 million NIMH grant to recruit 400 more families by 2007. And the private group has agreed to pool its samples with others available for free from the federal agency.
"The numbers of samples in (the repository) will increase dramatically over the next few years," says Steve Foote, who directs neuroscience and basic behavioral science at the institute.
Researchers are fairly confident that with enough genetic material, money and manpower, they will find the most important autism genes in the next few years, UCLA's Geschwind says.
But finding the genes won't mean instantly understanding autism. Scientists will have to learn what the culprit genes do and how they can go wrong.
Then they'll need to learn how environmental factors, before or after birth, interact with genes to produce autistic traits. "It could be as simple as a hormonal imbalance, something about the womb environment," Shih says. Vaccines, suspected by some, have not been shown to be a factor in several large studies, he says. Infections or toxins might play roles. But, Shih says, "the bottom line is that we just don't know."
More scientists needed
Learning more will mean bringing in more scientists with expertise in brain development, Foote says. "Right now, there is a shortage of investigators" to do that kind of work, he says. "They are largely busy with normative developmental issues, just understanding the basics of how any brain gets put together."
But if the pieces do ever come together, some researchers and advocates envision a day when fetuses or babies could be tested for autism risks and treated before the damage was done. The treatments might include drugs, diets or more refined versions of the teaching methods already helping many autistic children.
While the work goes on, families hit hard by autism will struggle on.
Jean and James Yates of Westchester County, N.Y., gave blood for the autism project several years ago and remain hopeful that their contribution will help someone, maybe even their own two severely autistic sons. Dylan, almost 12, does not speak and communicates little, except with tantrums. Brother Robert, 10, can read and speaks a little, but mostly just to show off his arcane knowledge of geography.
"If you ask Robert 'What is the capital of South Africa?' he'll tell you," his mother says. "If he goes to the dentist and he's desperate, he'll yell 'Fire!' But he cannot say to you, 'I want to leave the dentist's office.' "
Maybe the research will help the boys' older brother or their four half-siblings, none of whom has children yet. If the family does carry autism susceptibility genes, "I'd like for them to know about it," Jean says.
In any case, she says, "when you are a parent of children like this, there are so many ways you feel helpless. But this is empowering. You know that somewhere down the line this is going to help someone."
Says Geschwind: "We are going to find the major pathways that cause the disease. ... The bridge to treatment may be hard to cross. But you can't get there without the genes."
[ Post a Reply to This Message ]
|
Feedback: 