Autism: the statistics are staggering. The disease affects one in 110 children, and the figures are on the rise. Boys are four times more likely than girls to have it. According to the National Institutes of Health more children will be diagnosed in the coming year with autism than with AIDS, diabetes, and cancer combined. Autism is a lifelong diagnosis and has been called the fastest growing developmental disability in America.

A landmark collaborative study between researchers at the Salk Institute for Biological Studies and the University of California, San Diego used human cells to replicate autism in the lab for the first time ever to study the origins and effects of the disease.

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"It is quite amazing that we can recapitulate a psychiatric disease in a Petri Dish," says lead author Fred Gage, Ph.D.

In the study, scientists isolated Rett neurons. Rett syndrome is a rare and severe form of autism that only affects girls. "Being able to study Rett neurons in a dish,” says Gage, “allows us to identify subtle alterations in the functionality of the neuronal circuitry that we never had access to before."

According to the nonprofit agency Autism Speaks, there is no medical detection or cure for autism.

The Salk/UCSD study may change that.

"We show very clearly that autism is a biological disease that is caused by a developmental defect directly affecting brain cells," says lead author Alysson Muotri, Ph.D., an assistant professor in the Department of Molecular and Cellular Medicine at the UCSD School of Medicine. The problem, she says, is immediately recognizable in the neurons of an affected patient.

In other words, says study first author Carol Marchetto, Ph.D., a researcher in the Laboratory of Genetics at the Salk Institute, “You don’t need to see the context of the disease to see the deficiency.

“If you think about it, we were able to isolate cells from the patient, make neurons from them, and see the phenotype [autistic behavior.] On top of that, we were able to test a few drugs that would ameliorate the behavior.”

And all of that, Marchetto says, took place in just over two years.

“We are not where we can take the drugs that we found [to be effective] and use them directly in the patient yet. That is in the future. But,” she says “treatment is a possibility.”

Treatment, meaning a restoration to full-functioning rather than the standard regime of behavior modifications and maintenance drugs that are currently used to keep autistic individuals in balance? Marchetto says yes.

“We think this could be possible.” The medications tested by the research team improved the faulty connections. “We were able to rescue those neurons.”

Even though autism was first described in the 1940s, scientists still don’t know what causes it. That remains the big white elephant in the room. At various times the finger has been pointed at childhood vaccinations, genetics, environmental factors, better diagnostics, and even bad parenting.

“The scientific community does not currently think that vaccines are the problem,” says Marchetto. Nor, she says, is bad parenting the cause. She says the individuals in the Salk study all have a mutation on a specific gene. But, not all autistic children do.

“The great majority of autistic kids do not have a clear gene involved with the disease.”

In the past, study of autism has been limited to the brains of people with autistic spectrum disorders via imaging technologies or postmortem brain tissues. Now, the ability to obtain cell samples from patients' skin cells, which can be encouraged to develop into the cell type damaged by the disease, gives scientists an unprecedented view of autism.

As a result, researchers in the Salk/UCSD study learned that the numbers of neurons are the same in both non-autistic and autistic patients. The difference lies in the connections between neurons.

“In an autistic patient,” says Marchetto, “the connections are altered.

The numbers of neurons are not different in autistic kids. The kids are still functional. They are able to walk around and so on. But the connection between the neurons, she says, is where the difference is evident.

“We were surprised. We were not expecting this result. We weren’t expecting to see a defect in the neurons.” By comparison, she says there are no obvious changes in the behaviors of neurons of Alzheimer’s or Parkinson’s patients.