By Anita Manning, USA Today
A major U.S.-financed study designed to unearth the roots of autism will track 100,000 babies in Norway to identify biological and environmental factors that could combine to cause autism and other developmental disorders.
The Autism Birth Cohort, led by researchers at the Mailman School of
Public Health at Columbia University, will follow kids and their parents
for five years, beginning during the mother’s pregnancy.
Ultimately, the work could produce the kind of information on risk
factors for developmental disorders that the landmark Framingham Heart
Study did for stroke and heart disease, says W. Ian Lipkin of Columbia, the
autism study’s lead investigator.
Researchers will collect information on exposures to toxins,
including mercury, which has been suspected as a factor in autism, as well as diet, vaccines, babies’ birth weight and head circumference, and volumes of
other data that can be analyzed to compare children who develop autism with those who do not.
The causes of autism have long baffled investigators and frustrated
parents. The mystery has led to wide speculation that childhood vaccines,
viral infection or environmental toxins play a role, though scientific
evidence has not been conclusive.
The new study, outlined at a meeting at Columbia University on
Monday, is being conducted within a larger project instituted by the Norwegian Institute of Public Health. That initiative began recruiting pregnant
women in 1999 for a long-range study to track a variety of childhood and adult diseases.
Women are enrolled at the time of a prenatal ultrasound, usually at
17 weeks gestation. Mothers and fathers answer questionnaires on their health habits and nutrition, and blood samples are taken periodically from
parents and child. As of January, 33,656 babies had been enrolled, along with
their parents.
The National Institute of Neurological Disorders and Stroke, part of
the National Institutes of Health, will provide $13 million over five
years for the autism project, says program director Deborah Hirtz. A similar
study is planned in the USA, she says, but it’s just in early discussion stages.
By partnering in the Norwegian study already in progress, the
project can begin gathering and analyzing data right away, Lipkin says. He expects the first significant data to be available as early as next year.
“We will potentially reveal all sorts of interactions between the
environment and genes,” he says. The main focus is on autism, but
“ultimately we’ll be looking at disorders like ADHD (attention deficit
hyperactivity disorder), dementia” and more, he says.
Scientists believe autism and related conditions grouped under the
name Autism Spectrum Disorder result from a genetic predisposition
triggered by some as-yet-unknown environmental exposure. Infections or exposure to certain substances before or shortly after birth may result in diseases that appear later, Lipkin says. Timing of such exposures may also play a role, he says.
The study’s design allows scientists to “look during gestation,
where some of the roots (of autism) may appear,” Lipkin says. “If we can find
what puts kids at risk, we can develop interventions,” including medications or behavior changes.