BehindTheMedspeak: Is autism acquired or inherited?

Recent work published in the American Journal of Medical Genetics suggests it's largely inherited.

These findings are highly controversial, because there are many who believe that environmental causes - such as contaminated vaccines - are to blame.

For every paper blaming vaccines or environmental causes, there's one refuting them.

No matter the cause, autism is definitely on the rise, occurring 10 times more frequently now than in the late 1980s.

One in every 250 children born in the U.S. has some form of autism, which is proving to be a very broad-spectrum diagnosis, rather than the limited, focal constellation of symptoms previously considered diagnostic.

Over 1.5 million Americans are believed to have some form of the syndrome.

The incidence is increasing 10%-17% every year, such that 4 million Americans will suffer from it within a decade.

Scientists have long believed that genetics play a role in the occurrence of autism, because identical twins are more likely to share the diagnosis than fraternal twins.

Scientists led by Yong-hei Jiang at Baylor University College of Medicine suggest many cases of autism can be tracked to two or more principal genes, probably including one known as the Angelman gene.

"We believe that this model is highly likely to apply to some small fraction of autism cases, but more importantly, we propose that it will explain the majority of cases of autism."

[via Victoria Griffith and The Financial Times]