Latest TIME article...

[Guest guest]

New Clues to Autism's Cause

Thursday, Jul. 10, 2008 By _CLAUDIA WALLIS_ (javascript:void(0))

A participant eats during a day program for autistic adults.

M. Cohen / Corbis

(javascript:void(0))

(http://www.sphere.com/search?q=sphereit:http://www.time.com/time/health/article\

/0,8599,1821595,00.html?iid=chix-sphere)

(http:/

/www.addthis.com/bookmark.php?v=12 & winname=addthis & pub=timecom & s= & url=http://www\

..time.com/time/health/article/0,8599,1821595,00.html & title=New%20Clu

es%20to%20Autism\'s%20Cause%20-%20TIME)

(http://buzz./article/time/http%3A%2F%2Fwww.time.com%2Ftime%2Fhealth%2F\

article%2F0%2C8599%2C1821595%2C00.html)

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.

Walsh, chief of genetics at Children's Hospital Boston and an author of the

paper.

_Finding and Fighting Autism Early _

(http://www.time.com/time/health/article/0,8599,1677611,00.html?iid=sphere-inlin\

e-sidebar)

A teacher plays with an autistic child during a training session in an

equestria...

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. 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. "

*

(http://ad.doubleclick.net/click;h=v8/36f9/0/0/*/c;200882034;1-0;0;17870223;1844\

6-336/15;25742051/25759905/2;;~okv=;rsseg=10025;rsseg=10010;rsseg=1

0001;aid=1821595;ch=health%20 & %20science;ptype=content;ctype=article;sz=336x15

;path=time;path=health;~aopt=2/1/ff/0;~sscs=?http://ebm.cheetahmail.com/r/regf

2?a=0 & aid=1078532063 & n=1?iid=336x15_newsletterA)

(http://ad.doubleclick.net/click;h=v8/36f9/0/0/*/j;204935050;7-0;0;17870223;4307\

-300/250;27041437/27059294/1;;~okv=;rsseg=10025;rsseg=10010;rsseg=10001;aid

=1821595;ch=health%20 & %20science;ptype=content;ctype=article;sz=336x280,336x85

0,300x250,300x600;path=time;path=health;~aopt=2/1/ff/0;~sscs=?http://www.healt

h.com/health/condition-article/0,,20188175,00.html?xid=TD27B & utm_source=time & u

tm_medium=cpm_banner & utm_content=therapist_300x250.jpg & utm_campaign=ti)

" Ms. Michele "

**************Get the scoop on last night's hottest shows and the live music

scene in your area - Check out TourTracker.com!

(http://www.tourtracker.com?NCID=aolmus00050000000112)