Genetically-modified monkeys with autism created
Scientists in China say they have created monkeys with a version of autism by genetic engineering, an achievement that could make it easier to test treatments for the condition.
Zilong Qiu’s team at the Shanghai Institutes for Biological Sciences has generated more than a dozen monkeys with a genetic error that in human children causes a rare syndrome whose symptoms include mental retardation and autistic features, such as repetitive speech and restricted interests.
“The monkeys show very similar behavior [to] human autism patients,” Qiu said. “We think it provides a very unique model.”
Years of studies with mice suffering from autism-like disorders have provided disappointingly few leads on how to solve the problem in people. But mice have quite different brains from humans – for example, they do not have a prefrontal cortex, the brain area where some human psychiatric disorders seem to be centered.
Qiu says that with the monkey model, scientists would now be able to study what brain networks had been disrupted, as well as try out treatments, such as deep-brain stimulation. Qiu’s group is also about to attempt to reverse the symptoms it created by erasing the genetic error in live animals. That could be done using new genome-editing technologies, such as CRISPR, he says.
Genetically altered monkeys have been reported previously, however, Qiu’s report appears to be the first time that researchers have generated enough animals to observe stereotypical behavioral changes.
Some scientists questioned whether the model developed in China was close enough to autism to really shed any light on human disease. Although the monkeys exhibited common behaviors, like repetitive circling in their cages, these are not the same as those displayed in human children, says Huda Zoghbi, whose lab at the Baylor College of Medicine discovered in 1999 that damage to the MECP2 gene causes Rett syndrome, a form of autism affecting girls. More typical symptoms like seizures were absent, she said, while the monkeys’ circling doesn’t have an analog in humans.
John Spiro, deputy scientific director of the Simons Foundation Autism Research Initiative in New York, says he believes scientific leaders remain divided over how helpful primate models of autism will be. “There is a sentiment that you are never going to generate enough animals to be able to do the really important experiments,” he says. “But a lot of people feel extraordinary strongly that rodents aren’t good enough. I would say the smartest minds in the field say we have got to do this.”
