Autism spectrum disorders (ASD) affect about one percent of the world's population and are characterized by a range of difficulties in social interaction and communication. A team of researchers led by Gaia Novarino, Professor at IST Austria, has identified a new genetic cause of ASD. There are many different genetic mutations causing autism, and they are all very rare. A new autism-linked gene was not only revealed, but it also identified the mechanism by which its mutation causes autism. Mutations in other genes share the same autism-causing method. They were able to identify mutations in a gene called SLC7A5 in several patients born to consanguineous marriages and diagnosed with syndromic autism. SLC7A5 transports a certain type of amino acids into the brain. Researchers studied mice in which SLC7A5 is removed at the barrier between the blood and the brain, to understand how mutations of SLC7A5 lead to autism. They removed the gene from the mice and discovered that it caused an interference with protein synthesis in neurons. The mice showed reduced social interaction and behavioral changes. The researchers reintroduced the missing SLC7A5 gene into the mice and after three weeks, improvements in behavior were seen. Researchers found a potential treatment for a form of ASD only in mice. It is going to take many more years of research until this process can be performed on human patients. Before the study, autism spectrum disorders were always thought to be irreversible conditions. The way they treated symptoms in the mice cannot be directly used in humans. It showed that some of the neurological complications presented by mice missing SLC7A5 can be rescued. So, it is possible that patients may eventually be treated as well.
The fact that researchers found a potential treatment for a form of ASD only in mice is still a great thing. That shows we are one step closer in finding a treatment for humans. Hopefully in a few years, there will be results in potential treatments for autism spectrum disorders for humans.