An international team of researchers led by Gaia Novarino, a scientist at the Institute of Science and Technology, Austria, discovered a new genetic cause for autism spectrum disorder.
Autism Spectrum Disorder In Humans
About 1 percent of the population in the world is currently suffering from autism and experiences a range of debilitating symptoms including difficulties in communication and interaction with people. Novarino said that autism is caused by a variety of genetic mutations and the heterogeneity makes it tedious for development of effective treatment for the condition.
However, a new gene linked to autism is discovered in the current study and the researchers have also unraveled the mutation of the gene that results in the disorder. It is also noted that other gene mutations that cause autism could be sharing a similar mechanism.
SLC7A5 And Autism Spectrum Disorder
It was found that syndromic autism in patients born to parents who have had consanguineous marriages had mutation called SLC7A5 in a novel gene, noted the study's co-author Dr. Caglayan.
The SLC7A5 helps in transporting an amino acid commonly known as branched-chain amino acids (BCAA) into the blood. To check the role of SLC7A5, the researchers conducted mice experiment where the SLC7A5 near the blood brain barrier was removed, which eventually decreased the amount of BCAA transported into the brain.
As a result, the mice developed difficulty in social interaction and exhibited symptoms similar to mice models with autism. The investigators also found in earlier studies that a gene mutation that caused the breaking down of BCAA was associated with health outcomes including epilepsy, autism spectrum disorder and intellectual disability.
Novarino said that not all the genes involved in causing autism have impact on amino acids since these types of autism disorder are less common. However, the researcher noted that there is a possibility that at least a few genes that cause autism could belong to this group.
Researchers Treat Autism Induced In Mice
Surprisingly, the researchers were able to treat the SLC7A5 related neurological disorder induced in mice near the blood and the brain barrier. For the purpose of treatment, the investigators gave BCAA into the brain of the mice for a period of three weeks. At the end of the treatment period, the mice seemed to show improvements in their overall behavior.
"Our research found a potential treatment for certain symptoms presented in this form of ASD in mice but translation into a treatment for ASD patients will require many years of additional research," said Dora Tarlungeanu, the study's first author, in a press release.
The study was published in the journal Cell on Dec. 1.