Blood test for autism in early stages

Improvements in genetic testing may make the diagnosis process for autism more efficient.
Improvements in genetic testing may make the diagnosis process for autism more efficient.
STORY HIGHLIGHTS
  • A new experimental test may detect autism, based on gene expression differences
  • The blood-based test appears to predict autism relatively accurately among boys
  • It's been licensed to a company which will start clinical trials next year

(TIME.com) -- Earlier detection of autism, relying on markers in the blood, may help more children to take advantage of helpful behavioral therapies.

Diagnosing autism currently requires hours of observation by clinicians and a far from objective series of behavioral measures, but improvements in genetic testing could make the process more efficient.

In a study published in the journal PLOS ONE, researchers from Children's Hospital Boston describe a new experimental test to detect the developmental disorder, based on the differences in gene expression between kids with autism spectrum disorder (ASD) and those without the condition.

The blood-based test appears to predict autism relatively accurately, at least among boys, and has already been licensed to a company, SynapDx, for commercial development. In an e-mail statement to TIME, a spokeswoman for SynapDx said the company plans to start clinical trials of the new test in early 2013.

TIME.com: Autism studies confirm genetic complexity and risk for older fathers

The new blood test for autism is intriguing, researchers say, because it seems to be at least as effective as any other genetic test for autism that doctors currently use. Scientists believe that autism has some genetic basis, based on genes that have been associated with the disorder, and the fact that the condition seems to run in families.

"A week does not go by where you don't hear about a genetic mutation that has been linked to autism in at least a few families," says Isaac Kohane, a pediatric endocrinologist and computer scientist at Children's Hospital Boston, and the senior study author on the new article in PLOS ONE. Kohane is a scientific adviser for SynapDx, but says he does not own any stock in the company.

But autism is a complex condition, he says, with many possible genetic determinants. And the precise genetic mechanism, or more likely mechanisms, are still poorly understood.

But to get a better idea of which genetic changes might be most relevant to the disease, Kohane and his colleagues compared 66 patients with ASDs and 33 similar patients who were not affected by the disorder. Because they couldn't analyze the participants' brain tissue, they relied on their blood as a proxy for revealing any differences.

And indeed, they found certain markers in the blood of autistic participants that did not appear in those without the disorder. They traced these to 489 genes and narrowed that list down to 55 genes that could predict autism in about two-thirds of those with the disease.

TIME.com: Studies: New clues to the genetic roots of autism

"There are a lot of different mutations involved, and a lot of different pathways that seem to be involved in autism," Kohane says. Those genetic pathways included some known to be related to learning, and some linked to immune function.

"The fact that not all kids had both, and some kids would be more abnormal in immunological pathways and others would be more abnormal in (another pathway) spoke, I think, to the genuine heterogeneity of the disease," Kohane says.

"In that respect, autism is beginning to look a lot like what the cancer biologists are telling us about breast cancer, or lung cancer," he says. "There may be hundreds of different molecularly defined cancers, which each have their own specific optimal treatment." Similarly, autism spectrum disorders, too, may have diverse genetic roots, and appear clinically in slightly different ways from one patient to another.

TIME.com: Gene expression in the brain offers clues to autism's roots

Today, 1 in 88 kids suffers from an autism spectrum disorder, and prevalence has soared over the last 30 years, although it's not clear why. Diagnosing the disease early is important because it allows children to take advantage of behavioral intervention programs that can lead to higher IQ scores and improvements in language. Kohane says the blood test could identify those at risk of autism well before symptoms appear around age 2, and help these children access potentially beneficial therapies.

The test, however, is still in early stages of development. Kohane says that its accuracy (at around 70% in a high-prevalence, predominantly male sample) is high enough to be clinically useful among kids with a suspected developmental disorder.

But he stresses that the test as it stands still generates too many false positives, or people mistakenly identified with the condition when in fact they don't have it, for the test to be used as an autism screening tool among all children. If the current results are confirmed, that may take a few more years.

This story was originally published on TIME.com.

A blood test for autism?

&copy 2012 TIME, Inc. TIME is a registered trademark of Time Inc. Used with permission.

0
Comments »
  • Print
  • Email
  • More sharing
Disclaimer: Opinions expressed here are those of the writers and do not reflect those of Capitalbay. Capitalbay accepts no responsibility legal or otherwise for their accuracy of content. Please report any inappropriate content to us, and we will evaluate it as a matter of priority.
What's next
By CapitalBay Online 12/07/2012 00:12:00

ENTERTAINMENT

What was he keeping in there? Prince's $300m music vault deep inside Paisley Park 'is drilled open after secretive singer took the combination to his grave'

Trust appointed to look after Prince's estate has ordered vault to be opened Workers used drills to open it after singer took combination to the grave It

Beyonce unexpectedly cancels Formation World Tour concert in Nashville

Beyonce has unexpectedly cancelled her Formation World Tour gig next week in Nashville, Tennesse. The news was announced Friday by concert promoter Live Nation, but no

Kelly Ripa makes joke about 'contract negotiations' in front of Michael Strahan

Ripa returned to Live on Tuesday after a week away -following news her cohost Strahan was leaving the show for GMA On Tuesday she said ABC,

Artist and Beyoncé Collaborator Laolu Senbanjo An Overnight Media Sensation

While no one can ignore the impact of Beyoncé’s newest project, the music wasn’t the only thing that the superstar was introducing to her audience.

Johnny Manziel attends Justin Bieber concert hours after being indicted in alleged attack on ex-girlfriend

Johnny Manziel, 23, was indicted Tuesday in Dallas on assault charges His ex says the former NFL player hit her so hard she lost her hearing  Later

Prince 'was diagnosed with AIDS 6 months before he died and refused treatment'

Prince contracted HIV in mid-90s but condition developed into AIDS six months ago, anonymous sources have claimed Artist 'did not get treatment because he thought God

Beyonce's Becky lyric 'refers to composite of women Jay Z cheated with during marriage'

They're keeping the whole world guessing as to the identity of  'Becky with the good hair.' But rather than referring to a single woman who had

Recent Comments