Friday, July 11, 2008

There may be hundreds of varieties of autism

In the first year after Nicky was diagnosed I wanted more than anything to know what the future held. What would my Nicky look like in 3 years, 5 years as an adult? As I visited classrooms and programs I would focus in on the ASD kids and each time I imagined they were Nicky. I cried when I saw the kids who were severe and I felt increased hope when I saw the high functioning children. Through my eyes they were all Nicky, because I just didn’t know. How would he respond to therapy, how much would the autism impact his life, would he get better, would he be self sufficient? I wanted to find a kid just like him who could be my model. I remember thinking if I could just find a kid who presented just like Nicky, was a few years older, had the same intervention, I would have a road map. I could make a plan, I could learn what might work, I could prepare for the future. But such a kid NEVER materialized. There were lots of kids with ASD tendencies and behaviors similar to Nicky, but the severity and the intensities were different in each of them. In addition they all had different medical challenges. Nicky had severe food allergies and a seizure disorder. Some of the kids never developed typically, some developed slowly and my Nicky was talking and interacting and regressed almost overnight. Finally I learned that the kids seemed to fall into groups, but even within the groups there were no two alike. Just like all of the rest of us, we are all individuals and so are our kids.

In hindsight, I am grateful that I never found such a kid, because such a child might have given me amazing hope, or a caused me to accept a false future. Without any model I was forced to live one day at a time, and do all that I could everyday.

Knowing how different all of the children were I’ve always thought we must be dealing with more than one kind of autism, or different diseases/disorders that just had shared characteristics of autism. It just didn't seem possible that all the children I met with ASD had exactly the same disease or disorder. So for years I’ve been fussing about this and waiting for science to respond. Today I found this article science is beginning to understand these difference, as they agree that there are probably hundreds of different types of autism. Seems to me this is a big step, maybe not toward a cure, but toward getting each of our children the individual care they deserve.

It’s a good read. Enjoy

New Clues to Autism's Cause

A participant eats during a day program for autistic adults.

What exactly is going awry in the brains of people who have autism? The answer is very slowly coming into focus. A paper published in the current issue of Science by researchers at Children's Hospital Boston and members of the Boston-based Autism Consortium identifies five new autism-related gene defects. Already, more than a dozen genetic defects have been found to be associated with autism spectrum disorders, which affect about 1 in 150 children, according to the Centers for Disease Control and Prevention. But the good news, say the Boston researchers, is that many of the genes are beginning to fit into a pattern. "While it might seem discouraging that it's a growing list of genes, we can be encouraged that a common pathway is emerging," says Dr. Christopher Walsh, chief of genetics at Children's Hospital Boston and an author of the paper.

Researchers looked at autism-related genes found in large families in the Middle East and Turkey. Big families in which cousins sometimes marry cousins are ideal for studying recessive genes. Though the newly identified genes are located in far-flung regions on the 23 human chromosomes, they are related in function: most play a role in learning. These genes are active in creating, reinforcing or modifying synaptic pathways in the brain — physical and biochemical changes that occur when we learn something new. The implication of this work is that autism may fundamentally amount to molecular defects in learning.

Symptoms of autism typically emerge during the first five years of life — a period when a child normally picks up language, social skills and many other new abilities. Scientists call this kind of growth "experience-dependent learning," and researchers know that it is associated with enormous changes in brain circuitry. At least 300 genes switch on and off to regulate experience-dependent learning. Defects in any number of them could conceivably result in some symptoms of autism. There may be hundreds of varieties of autism. From what researchers have seen so far, says Morrow, "It looks like almost every child with autism is different from the next — a different gene is mutated in almost every child."

One encouraging finding: most of the genetic defects identified in the Middle Eastern families were not in the business part of the gene — the part that codes for a critical brain protein. Instead the defects lay mainly in adjacent regions that turn the gene fully or partially on and off. This suggests that certain therapies or drugs could help normalize the activity of these genes, according to Dr. Eric Morrow of Massachusetts General Hospital, one of the lead authors of the paper. In fact, Morrow suspects that early intervention programs for children with autism involving intensive instruction in speech and social behavior may work by altering the expression of affected genes. (This idea is supported by research with mice, which has shown that providing a rich, stimulating environment directly affects gene expression in the brain.)

Autism, like most mental disorders, is largely defined by external behaviors rather than a clear biological understanding. Genetic studies like this one, observes Morrow, "offer a fantastic opportunity to define the pathology." To begin to give an explanation to families, he says, "is a big deal."

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