Examining the Overlap between Autism Spectrum Disorder and 22q11.2 Deletion Syndrome

Abstract

22q11.2 deletion syndrome (22q11.2DS) is a genomic disorder reported to associate with autism spectrum disorders (ASDs) in 15–50% of cases; however, others suggest that individuals with 22q11.2DS present psychiatric or behavioral features associated with ASDs, but do not meet full criteria for ASD diagnoses. Such wide variability in findings may arise in part due to methodological differences across studies. Our study sought to determine whether individuals with 22q11.2DS meet strict ASD diagnostic criteria using research-based guidelines from the Collaborative Programs of Excellence in Autism (CPEA), which required a gathering of information from three sources: the Autism Diagnostic Interview-Revised (ADI-R), the Autism Diagnostic Observational Schedule (ADOS), and a clinician’s best-estimate diagnosis. Our study examined a cohort of children, adolescents, and young adults (n = 56) with 22q11.2DS, who were ascertained irrespective of parents’ behavioral or developmental concerns, and found that 17.9% (n = 10) of the participants met CPEA criteria for an ASD diagnosis, and that a majority showed some level of social-communication impairment or the presence of repetitive behaviors. We conclude that strictly defined ASDs occur in a substantial proportion of individuals with 22q11.2DS, and recommend that all individuals with 22q11.2DS be screened for ASDs during early childhood.

Speech-Language Disorders in 22q11.2 Deletion Syndrome: Best Practices for Diagnosis and Management

“…Autism spectrum disorder and subthreshold autistic symptomatology also show increased prevalence ranging from 20% (Fine et al, 2005) to 50% (Vorstman et al, 2006). Using strict autism spectrum disorder diagnostic criteria, a prevalence of 17.9% was found with a majority of children showing some level of social communication impairment (Ousley et al, 2017). Frequently associated conditions include attention-deficit/hyperactivity disorder, anxiety, obsessive compulsive disorder, and later onset psychosis, including schizophrenia, which has been reported in up to 25% of those with 22qDS (Bassett et al, 2005(Bassett et al, , 2011Green et al, 2009;McDonald-McGinn et al, 2015;Schneider et al, 2014).…”

Williams syndrome, human self-domestication, and language evolution

“…Interestingly, children at risk or with ASD show reduced preference for infantdirected speech (Watson et al, 2012), this impacting negatively on language skills at later ages (Nadig et al, 2007;Paul et al, 2007;Watson et al, 2010). Evidence about WS children is not available, but compared to children with 22q11.2 Deletion syndrome, who commonly exhibit autistic features (Ousley et al, 2017), they express more positive emotions towards their mothers in a conflict interaction, higher levels of child's engagement, and enhanced reciprocity (Weisman et al, 2015).…”

Psychiatric disorders and autism in young children with 22q11.2 deletion syndrome compared to children with idiopathic autism

“…Previous studies on ASD and 22q11DS that relied only on parents’ interviews using the ADI-R [6,11,15] reported higher ASD rates in 22q11DS (20–50%), while the studies that used an observational diagnostic instrument like the ADOS [9,14] reported lower rates of ASD (0–18%), suggesting that adding observational measures of ASD to parent-report measures provide lower rates of ASD diagnosis in 22q11DS.…”

“…Several studies assessed the presence of ASD in individuals with 22q11DS and reported rates of ASD that varied greatly, i.e., from 7% to 50% [6,9,10,11,12,13,14,15]. Possible explanations for such variability include differences in the age of the subjects and in the tools used to assess ASD.…”