Research shows that although patients who have been diagnosed with an autism spectrum disorder have a higher burden of mutations in cancer-promoting oncogenes, they actually have lower rates of cancer.
Autism spectrum disorder is a general term for a group of disorders that affect brain development. Autism is characterized by impaired social interaction, verbal and nonverbal communication skills and repetitive behaviors. Autism is also one symptom of many inherited cancer syndromes caused by mutations in a single gene.
Researchers analyzed large, publicly available genomic databases of patients with autism and found that compared to a control set, autistic patients have significantly higher rates of DNA variation in oncogenes.
Researchers also discovered that patients with a diagnosis of autism are also significantly less likely to have a co-occurring diagnosis of cancer.
On one hand this result makes sense and on the other hand it is extremely perplexing.
Researchers used exome sequencing data from the ARRA Autism Sequencing Collaboration and compared that data to a control cohort from the Exome Variant Server database. Variants were not significantly enriched in tumor suppressor genes and in comparison rare coding variants within oncogenes were greatly enriched in the ARRA ASD cohort.
In order to ensure that the genetic differences were not simply technical artifacts but actually bona fide differences in genetic architecture in autism, researchers ran numerous controls. They found that individuals with autism had many more DNA variations in genes previously associated with autism, epilepsy and intellectual disability compared to control individuals.
There was no difference between the autism and control groups when the examined genes involved in unrelated conditions.
The findings raise questions that might have implications for new ways of treating both cancer and autism spectrum disorder.