CGH Findings in Children with Complex and Essential Autistic Spectrum Disorder.
Array-CGH finds a harmful DNA chunk in roughly one out of eight kids who have autism plus other medical signs.
01Research in Context
What this study did
Doctors ran array-CGH gene scans on kids with two kinds of autism. One group had complex autism with extra problems like seizures or odd facial features. The other group had essential autism with no extra signs.
They wanted to know how many kids in each group carried harmful chunks of missing or extra DNA.
What they found
About 13 out of every 100 complex-autism kids showed a harmful DNA chunk. None of the essential-autism kids did.
The DNA findings did not line up with IQ, language level, or autism severity scores.
How this fits with other research
Napoli et al. (2018) looked only at essential-autism kids and found the opposite link. In their group, kids who had harmful DNA chunks showed more autism symptoms and were more likely to be non-verbal.
The two studies seem to clash, but they tested different faces of autism. One study picked kids with added medical issues; the other picked kids with pure autism. That choice drives whether DNA chunks track with behavior.
Other papers like Qian et al. (2022) and Nickerson et al. (2015) keep showing that rare gene changes can sit behind autism plus extra problems, backing the idea that complex cases deserve a closer genetic look.
Why it matters
If a child has autism plus seizures, slow growth, or unusual facial features, order an array-CGH test. Expect about a one-in-eight chance of finding a clear genetic cause. The result may not predict IQ or language, but it gives families a reason and helps steer medical care.
Get CEUs on This Topic — Free
The ABA Clubhouse has 60+ on-demand CEUs including ethics, supervision, and clinical topics like this one. Plus a new live CEU every Wednesday.
Flag any client with autism plus unusual facial features, seizures, or growth delays for genetic consult and array-CGH testing.
02At a glance
03Original abstract
Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental condition with a strong genetic basis. We accurately assessed 209 ASD subjects, categorized in complex (47) and essential (162), and performed array comparative genomic hybridization to identify pathogenic and recurrent Copy Number Variants (CNVs). We found 117 CNVs in 75 patients, 11 classified as pathogenic. The complex ASD subjects have higher frequency of pathogenic CNVs with a diagnostic yield of 12.8%. Familiality, cognitive and verbal abilities, severity of autistic symptoms, neuroimaging and neurophysiological findings are not related to genetic data. This study identifies loci of interest for ASD and highlights the importance of a careful phenotypic characterization, as complex ASD is related to higher rate of pathogenic CNVs.
Journal of autism and developmental disorders, 2023 · doi:10.1016/j.pnpbp.2019.02.012