It isn't a general cure. It applies to a mouse form of a kind of autism found in one in 10,000 to 15,000 girls. Boys are swiftly killed by the disease. The most recent data shows that 1 in 150 children have an autism spectrum disorder and it is more common in boys than in girls - so only a fraction of 1% of autism cases are directly impacted by the discovery. Treatment was easier to devise in this kind of autism than others because scientists know precisely what causes this form of autism, a defect in the operation of specifically identified genes. This is a particularly nasty version of autism, however:
After its outset—usually within 18 months of birth—young girls suffering from the illness begin to display asocial symptoms similar to those of autism. RS [Rett Syndrome] primarily affects the nervous system and can eventually lead to problems with speech and movement, often leaving patients with a stiff gait or confined to a wheelchair. Symptoms can also include tremors and irregular breathing.
The scientists treated the mice with tamoxifen, a breast cancer drug, with great results.
All of the symptoms . . . were erased in the female mouse model. . . . "It's like a dream result, to me," marvels biologist Rudolf Jaenisch of the Massachusetts Institute of Technology's Whitehead Institute. "Even if you have the disease—and these animals were almost moribund—you can still rescue them."
There is no known cure for inappropriate use of similes by biologists at this time, perhaps because mice are not known to suffer from that disorder.
Don't try this at home with your Rett Syndrome afflicted child. While scientists eventually got a good result with a proper dosage of the drug, the trial and error process to determine the proper dose of the drug killed a lot of mice.
But, the good news is that one autism spectrum disorder may be headed for a cure in the foreseeable future.