Authors:
Taylor LJ, Maybery MT, Wray J, Ravine D, Hunt A, Whitehouse AJO
Authors notes:
Research in Autism Spectrum Disorders. 2015;11:56-62
Keywords:
Autism Spectrum Disorder, Behavioural phenotype, Simplex and multiplex families
Abstract:
Recent research suggests that different genetic pathways may operate for families with one child affected with Autism Spectrum Disorder (simplex ASD), compared to families that have multiple affected children (multiplex ASD).
In this study, we investigated possible differences in the behavioural phenotypes of probands from simplex and multiplex ASD families using parent-report and standardised behavioural measures.
Participants were 59 probands from multiplex ASD families (28 families), who were each matched on chronological age and sex with two probands from simplex families.
Probands from multiplex families had greater social impairment (measured using the Social Responsiveness Scale) and worse pragmatic language (on the Children's Communication Checklist-2) than probands from simplex families. However, the multiplex children had less severe symptoms than the simplex children on the ADOS-G, and a significantly higher proportion of multiplex children did not meet autism spectrum cut-offs on this measure.
These findings indicate that there are behavioural differences in children with ASD from simplex and multiplex families.
In addition, the results reveal an important discrepancy between parent-report and clinician observation of autistic-like characteristics in siblings of an affected child, which may have implications for the assessment and diagnosis of ASD.