Single nucleotide polymorphisms predict symptom severity of autism spectrum disorder.
A 29-SNP panel, led by rs878960 in GABRB3, gives a weak 67 % heads-up on autism severity—useful only as a side clue, not a stand-alone test.
01Research in Context
What this study did
Jiao et al. (2012) built a 29-SNP genetic score to predict autism severity. They tested it against the Childhood Autism Rating Scale (CARS). The model got 67 % of cases right—better than chance, but far from perfect.
One SNP, rs878960 in the GABRB3 gene, kept showing up as useful on its own.
What they found
The 29-SNP panel gave a weak but real signal. It sorted kids into mild versus severe groups with 67 % accuracy. rs878960 alone was the strongest single marker.
In plain words: genes added a small piece to the severity puzzle, not the whole picture.
How this fits with other research
Sugie et al. (2005) already linked a different gene (5-HTTLPR) to drug response in autism. Yun extends that idea—genes can predict phenotype, but now for natural severity instead of medication change.
Kamp-Becker et al. (2010) showed Asperger and high-functioning autism are just points on one continuum. Yun gives that continuum a genetic ruler, backing up the “severity is continuous” view.
Sun et al. (2015) proved standard tools like ADOS work in China. Yun tries the same validation job for a DNA-based tool, but with weaker results—67 % versus Xiang’s over-80 % agreement.
Farrant et al. (1998) remind us that parents and siblings often carry tiny autistic traits. Yun’s severity model could, in theory, be run on undiagnosed relatives to see if the same SNPs track sub-threshold quirks.
Why it matters
For now, you still need ADOS, ADI-R, and good clinical judgment. Yet keeping an eye on GABRB3 and related SNPs may one day sharpen early estimates of how much support a toddler will need. Until larger studies boost accuracy above 90 %, treat genetic severity scores as conversation starters with families, not final verdicts.
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Join Free →When you review a child’s genetics report, note any GABRB3 markers and file them under “possible severity hint,” then keep running your standard CARS or ADOS all the same.
02At a glance
03Original abstract
Autism is widely believed to be a heterogeneous disorder; diagnosis is currently based solely on clinical criteria, although genetic, as well as environmental, influences are thought to be prominent factors in the etiology of most forms of autism. Our goal is to determine whether a predictive model based on single-nucleotide polymorphisms (SNPs) can predict symptom severity of autism spectrum disorder (ASD). We divided 118 ASD children into a mild/moderate autism group (n = 65) and a severe autism group (n = 53), based on the Childhood Autism Rating Scale (CARS). For each child, we obtained 29 SNPs of 9 ASD-related genes. To generate predictive models, we employed three machine-learning techniques: decision stumps (DSs), alternating decision trees (ADTrees), and FlexTrees. DS and FlexTree generated modestly better classifiers, with accuracy = 67%, sensitivity = 0.88 and specificity = 0.42. The SNP rs878960 in GABRB3 was selected by all models, and was related associated with CARS assessment. Our results suggest that SNPs have the potential to offer accurate classification of ASD symptom severity.
Journal of autism and developmental disorders, 2012 · doi:10.1007/s10803-011-1327-5