Cognitive and Adaptive Profiles in Three Single-Gene Causes of Autism Spectrum Disorder and Idiopathic Autism Spectrum Disorder with Intellectual Disability

Poster Presentation
Thursday, May 2, 2019: 11:30 AM-1:30 PM
Room: 710 (Palais des congres de Montreal)
J. Zweifach1, L. Tang1, D. Halpern1, J. Foss-Feig1, I. Giserman-Kiss1, M. Mulhern1, S. M. Lurie2, J. Weissman1, M. L. Gorenstein1, H. Grosman1, M. A. Rowe1, E. Wilkinson1, E. Drapeau3, S. De Rubeis3, J. Buxbaum4, A. Kolevzon1 and P. M. Siper1, (1)Seaver Autism Center, Department of Psychiatry, Icahn School of Medicine at Mount Sinai Hospital, New York, NY, (2)Psychology, Ferkauf Graduate School of Psychology, Yeshiva University, Bronx, NY, (3)Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, (4)Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY
Background: Phelan-McDermid syndrome (PMS), ADNP syndrome, and FOXP1 syndrome represent three of the most common single gene causes of autism spectrum disorder (ASD) and intellectual disability (ID). As genetic testing becomes more accessible, a broader spectrum of individuals with single-gene causes associated with ASD are presenting to clinics, however, little is known about the cognitive and adaptive profiles of individuals with single-gene causes of ASD who are able to complete standardized measures of intellectual functioning and how those results compare to individuals with idiopathic ASD (iASD) and ID.

Objectives: To compare cognitive and adaptive profiles in children with iASD and ID relative to children with single-gene causes of ASD and ID.

Methods: Participants included 20 children with a single-gene causes associated with ASD including PMS (n=10), FOXP1 syndrome (n=7) and ADNP syndrome (n=3) and 15 children with iASD and ID. Participants were between the ages of three and 17 with full scale IQs below 70. Participants were selected based on their ability to complete standardized IQ testing as measured by the Stanford Binet Intelligence Scales, Fifth Edition, Wechsler Intelligence Scales for Children, Fifth Edition, or Differential Ability Scales, Second Edition. Those unable to complete age-appropriate IQ tests and one individual with single-gene ASD without ID were excluded from analyses. Adaptive functioning was measured using the Vineland Adaptive Behavior Scales, 2nd and 3rd Editions.

Results: There were no significant differences between single-genes associated with ASD and single-gene groups on verbal IQ (VIQ; p=.81), nonverbal IQ (NVIQ; p=.97), or full scale IQ (FSIQ; p=.43). Within and across groups, VIQ and NVIQ were similarly developedFSIQ ranged from 40-68 in the single-gene group (M=50, SD=9.34) and 40-69 in the iASD group (M=53 SD=10.54). Results from the Vineland indicated no significant differences on the Adaptive Behavior Composite (p=.47) or within individual domains (p-values >.13). Considering each single-gene group independently, the ADNP group was reported to display weaker communication skills relative to other groups, while socialization and daily living skills were reported as similarly developed across groups.

Conclusions: Our findings suggest similar cognitive and adaptive profiles in children with single-genes associated with ASD and mild-to-moderate ID compared to children with iASD and mild-to-moderate ID. Verbal and nonverbal abilities were equally developed in both groups, which diverges from reports of better developed NVIQ than VIQ in a number of ASD studies inclusive of individuals with a broader range of cognitive ability. Data collection in single-gene causes is ongoing and future studies will examine whether single-gene specific cognitive or adaptive profiles emerge.