Genetic Testing History in Adults With Autism Spectrum Disorder

Many genes have been identified in autism spectrum disorder (ASD). Yet how many adults with ASD receive recommended genetic testing and their outcomes is unknown. We investigated the percentage of adults with ASD with documented genetic testing in our ASD specialty clinic and the percentage with positive findings.

Adults were identified through search of our data repository and ASD diagnoses confirmed using record review by psychiatrists specializing in ASD. Patients were included (N = 630) who had at least one visit with a qualifying clinician between 5/1/2010 and 12/15/2020. Data were collected through manual retrospective record review.

Only 41% of the adults with ASD (261/630) had a documented history of genetic testing. Genetic testing was declined by patients or families for 11% of records and not recorded in 47%. Mean (SD; range) age for the 261 adults was 28.5 (5.3; 22-58) years; 26% were female and 73% had intellectual disability (ID). The genetic testing method was recorded in 91% (238). Only 54% of these patients had testing using a recommended method (chromosomal array, autism/ID sequencing panel, or exome sequencing). Few adults received testing with sequencing technologies. A genetic cause of ASD was found in 28%.

ASD-related genetic testing is underutilized in adults with ASD. Nearly half of the adults in our sample lacked documentation of genetic testing. Adults with ASD may benefit from having their genetic testing history reviewed in the clinic and the recommended testing performed.