Characterizing the autism spectrum phenotype in DYRK1A‐related syndrome

Likely gene‐disrupting (LGD) variants in DYRK1A are causative of DYRK1A syndrome and associated with autism spectrum disorder (ASD) and intellectual disability (ID). While many individuals with DYRK1A syndrome are diagnosed with ASD, they may present with a unique profile of ASD traits. We present a comprehensive characterization of the ASD profile in children and young adults with LGDs in DYRK1A. Individuals with LGD variants in DYRK1A (n = 29) were compared to children who had ASD with no known genetic cause, either with low nonverbal IQ (n = 14) or average or above nonverbal IQ (n = 41). ASD was assessed using the ADOS‐2, ADI‐R, SRS‐2, SCQ, and RBS‐R. Quantitative score comparisons were conducted, as were qualitative analyses of clinicians' behavioral observations. Diagnosis of ASD was confirmed in 85% and ID was confirmed in 89% of participants with DYRK1A syndrome. Individuals with DYRK1A syndrome showed broadly similar social communication behaviors to children with idiopathic ASD and below‐average nonverbal IQ, with specific challenges noted in social reciprocity and nonverbal communication. Children with DYRK1A syndrome also showed high rates of sensory‐seeking behaviors. Phenotypic characterization of individuals with DYRK1A syndrome may provide additional information on mechanisms contributing to co‐occurring ASD and ID and contribute to the identification of genetic predictors of specific ASD traits. Lay Summary DYRK1A syndrome has been identified as a genetic cause of autism spectrum disorder (ASD). We found that individuals with DYRK1A syndrome had high rates of ASD and intellectual disability (ID). Individuals with DYRK1A syndrome showed many similarities in ASD traits when compared to individuals with ASD and ID without a known genetic cause, but individuals with DYRK1A syndrome showed particular differences in social reciprocity, nonverbal communication, and sensory‐seeking behaviors.