Tuesday, September 23, 2008

NPR series on autism: Hope for Fragile X, autism in college and more.

Public radio has been running a series on cognitive disorders. You can read summaries and listen to audio on the npr web site. I assembled this list by visiting a few and checking out related links. It covers most of the programs over the past two years, the more recent ones are first.

Like millions of other NPR donors, I wish NPR provided downloadable MP3s rather than streaming audio. I must remember that the next time they hit me up for money.

I heard the most recent program on my commute this morning. It was on of those stories about parents, the Tranfaglia-Clapps in this case, who create a foundation and hound scientists to accelerate progress in their disorder. Alas, I’m no saint. These stories annoy me. Should I feel bad because I haven’t created a foundation for my kids?

Rationally, it’s not a good bet. Ironically, the Tranfaglia-Clapps were inspired by the movie “Lorenzo’s Oil”, but that was a movie. In reality the “oil” was a bust; the time and energy largely wasted except insofar as they supported new studies and research directions. That’s the hard thing about science and clinical research – there are lots of “busts”. There are many ways to spend one’s limited time and energy with special needs children, and time spent on developing a foundation has to be subtracted from competing priorities.

Even bad bets have winners though, and in this case the family’s small foundation made a starter grant to a neuroscientist casting around for money. Maybe Dr. Bear would have found his starter grant elsewhere, but chances are his work, at least, would have moved slower and taken longer. His initial results worked, and he was able to raise NIH funds….

Drugs Hint At Potential Reversal Of Autism : NPR

… every now and then, a basic scientist makes a discovery that changes human lives.

Mark Bear, who directs the Picower Institute for Learning and Memory at MIT, is one of those basic scientists. He's discovered a system in the brain that could change the lives of thousands of people with the genetic disorder known as Fragile X Syndrome.

Fragile X is a mutation on the X chromosome that can cause mental retardation and autism. Until now, there has been no treatment.

But Bear discovered that the mutation responsible for Fragile X appears to disrupt a system in the brain that regulates synapses — the connections between brain cells. He says the system works a bit like a car.

"You really need both the accelerator and the brake to properly function," Bear says. "In the case of Fragile X, it's like the brakes are missing. So even tapping the accelerator can have the car careening out of control."

Bear and other scientists have also identified several drugs that seem to correct the problem. The drugs don't replace the missing brakes in the brain. Instead, they limit acceleration by reducing the activity of a group of receptors on brain cells known as mGluR5 receptors.

The drugs have reversed most of the effects of Fragile X in mice. They are now being tried in humans. And at least one small study found that a single dose of a drug had an effect.

The implications for people with Fragile X are huge. If the drugs work, people with the disorder could see their IQs rise and their autism diminish.

"It's a dream come true to think that we have the prospect of having gone from really basic science discovery to a potential treatment," Bear says.

Bear's research was funded in part by a group called FRAXA. Katie Clapp and her husband, Michael Tranfaglia, started the group in the early 1990s as a way to help their son Andy, who has Fragile X Syndrome.

Clapp says she now has reason to hope that Andy, who is now 19, can get better.

"We're not expecting a miracle, or to make up for his 19 years of development," she says. "But if we can watch improvement happen, that's a dream."

We can cure damn near anything in mice, so the animal studies are just interesting.

There are lots of hits on mGluR5 and autism, including a 2007 TIME article. Here’s a 2005 review synopsis:

Purpose of review: This review will describe recent developments in the neurobiology of fragile X syndrome (FXS), the association between FXS and autism, and involvement in premutation carriers.

Recent findings: Metabotropic glutamate receptor 5 (mGluR5)-coupled pathways are dysregulated in individuals with FXS and this is thought to relate to the FXS phenotype. The mGluR5 model suggests that mGluR5 antagonists, including downstream effectors such as lithium, could be useful for treating FXS. Two forms of clinical involvement associated with the fragile X mental retardation 1 (FMR1) gene, autism and fragile X-associated tremor/ataxia syndrome (FXTAS), have received additional attention during the past year. One study has found that approximately 30% of individuals with FXS have autism; those with autism have lowered cognitive abilities, language problems, and behavioral difficulties compared to those with FXS alone. Furthermore, evidence is mounting that autism also occurs in some young males who have premutation alleles. Finally, males and occasional females with premutation alleles may develop a neurological syndrome with aging that consists of tremor, ataxia, peripheral neuropathy, and cognitive deficits. Significant brain atrophy and white-matter disease is usually seen. This new disorder (FXTAS) is thought to be related to elevated levels of abnormal FMR1 mRNA.

Summary: Full-mutation forms of the gene (> 200 repeats) can cause autism, learning disabilities, anxiety disorders, and mental retardation. Disorders associated with premutation forms of the gene (55-200 repeats) include, in addition to autism, FXTAS in older males and females, and premature ovarian failure.

My sense is that this sounds like a step along a road, but it might be a dead end. Progress, nonetheless.

I’ll take a look at the other programs over time and I’ll blog on any that are worthwhile. The next time NPR asks you for money, tell ‘em you’re going to hold back until they start providing MP3 downloads …

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