Assessment & Research

Delineating the profile of autism spectrum disorder characteristics in Cornelia de Lange and Fragile X syndromes.

Moss et al. (2013) · American journal on intellectual and developmental disabilities 2013
★ The Verdict

Cornelia de Lange and Fragile X syndromes often trip the SCQ ASD wire, but the symptom pattern is its own beast.

✓ Read this if BCBAs assessing ASD in genetic syndrome clinics or school teams serving CdLS/FXS students.
✗ Skip if Practitioners who work only with idiopathic ASD and rarely see genetic syndromes.

01Research in Context

01

What this study did

The team gave the Social Communication Questionnaire to people with Cornelia de Lange syndrome and Fragile X syndrome.

They wanted to see how many met the ASD cutoff and which symptoms stood out.

The study was small: a case series with no control group.

02

What they found

About 8 in 10 people in each syndrome group scored above the ASD cutoff on the SCQ.

Yet the pattern of answers was not the same as typical idiopathic ASD.

Each syndrome showed its own mix of social, communication, and repetitive quirks.

03

How this fits with other research

Moss et al. (2009) already said ASD in genetic syndromes looks different from regular ASD. Greer et al. (2013) now adds hard numbers for CdLS and FXS.

Jones et al. (1998) found only 25% of young FXS boys met the CARS autism cutoff. The new SCQ rate is far higher. The gap is not a true clash: CARS was given by a clinician to preschool boys, while the SCQ was a parent form covering lifetime traits.

Heald et al. (2020) later showed these same syndromes also carry unique sensory profiles. Together the papers argue: screen, then dig deeper to see the real picture.

04

Why it matters

A high SCQ score in CdLS or FXS does not equal classic ASD. Expect atypical social strengths, different language gaps, and sensory twists. Use the score as a red flag, not a label. Then watch real-life behavior, add syndrome-specific probes, and plan teaching or sensory supports that fit that child, not a generic ASD manual.

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If a child with CdLS or FXS scores high on the SCQ, re-interview caregivers about social enjoyment and sensory quirks before writing goals.

02At a glance

Intervention
not applicable
Design
case series
Sample size
454
Population
autism spectrum disorder, intellectual disability, other
Finding
not reported

03Original abstract

An atypical presentation of autism spectrum disorder is noted in Cornelia de Lange and Fragile X syndromes, but there are few detailed empirical descriptions. Participants in this study were individuals with Cornelia de Lange syndrome (n  =  130, M age  =  17.19), Fragile X syndrome (n  =  182, M age  =  16.94), and autism spectrum disorder (n  =  142, M age  =  15.19), who were comparable on chronological age. Using the Social Communication Questionnaire, the proportion meeting cutoff for autism spectrum disorder and autism was 78.6%, and 45.6%, respectively, in Cornelia de Lange syndrome and 83.6% and 48.6% in Fragile X syndrome. Domain and item analyses indicate differing, atypical autism spectrum disorder profiles in Fragile X and Cornelia de Lange syndromes. A limited association between adaptive behavior and autism spectrum disorder was identified in all groups. The findings have implications for intervention in genetic syndromes and conceptualization of autism spectrum disorder in the wider population.

American journal on intellectual and developmental disabilities, 2013 · doi:10.1352/1944-7558-118.1.55