Navigating the genetic complexity of autism spectrum disorder (ASD) with insights from Labcorp's Reveal® SNP Microarray Pediatric Test
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder typically characterized by deficits in social behaviors and communication skills emerging within the first three years of life. Given ASD’s spectrum nature and the absence of clear biomarkers or diagnostic measures, it’s important to understand ASD’s genetic origins.
Determining ASD’s genetic etiology can help support diagnosis and condition management for children with autism. This knowledge streamlines management decisions and also helps guide families to tailored support, which can reduce unnecessary tests and interventions and expediate access to appropriate options.
Professional societies recommend SNP microarray as the first-line test for pediatric patients presenting with symptoms of ASD.1-3 Labcorp’s recently enhanced Reveal SNP Microarray Pediatric provides high-resolution, genome-wide coverage to identify copy number and copy neutral abnormalities. Read on to discover the benefits.
Earlier ASD diagnosis: Empowering providers and shortening wait times
Currently, children with suspected ASD can face a long wait (6-18 months) to see a specialist after receiving a referral. Limited access, especially in rural areas, further extends this timeline. This delay can be significantly reduced by offering testing like Reveal SNP Microarray Pediatric alongside fragile X testing in the primary care setting. This approach offers several benefits:
-Microarray gives providers valuable insights to help guide initial discussions and support families
-Earlier testing prepares patients for their specialist appointment sooner, potentially shaving months off the diagnostic journey
Alignment with guidelines: Genetic testing in ASD evaluation and management
The American College of Medical Genetics and Genomics (ACMG) advocates for chromosomal microarray testing as the first tier of genetic testing in the ASD workup, coupled with fragile X testing in males and additional gene sequencing for specific genes like PTEN and MECP2 in certain cases.4
Depending on the results, further referral to a geneticist and/or genetic counselor may be warranted, supporting comprehensive management and informed decision-making.4,5 Through these partnerships, healthcare providers can further enhance their support for families during the wait for specialist appointments.
Experience and precision: Labcorp’s Reveal SNP Microarray Pediatric
The Reveal SNP Microarray Pediatric test is a genome-wide analysis using 2.8 million probes, including over 2 million probes specifically designed to detect structural variations and nearly 750,000 SNP probes. And our comprehensive variant database helps keep variants of uncertain significance (VUS) rate low, at approximately 7.4% in pediatric cases. This comprehensive approach allows us to identify both copy number variations and copy-neutral abnormalities, providing invaluable insights into potential genetic causes of ASD.
We understand the challenges of collecting blood samples from young children, so sample collection with buccal swabs is available. Because we use a single microarray platform for prenatal and pediatric testing, we can reanalyze prenatal samples after birth if there is a clinical indication or new symptoms. This minimizes the need for new samples or additional costs.
With over 335,000 total microarrays performed to date, including more than 201,000 specifically for pediatric patients, our team has a wealth of experience in applying this technology and provides reliable and accurate analysis.
An important first step in the diagnostic journey
Microarray provides information to support the diagnosis of children with autism. However, it's important to note that more comprehensive genetic tests such as whole exome sequencing (WES) and whole genome sequencing (WGS) are available and can offer a more in-depth analysis. These tests compare the child’s exome or genome with that of their biological parents,6 while also analyzing chromosomal copy number variations like microarrays. In this way, WES and WGS often improve the detection of genetic variations contributing to ASD.7
While guidelines may eventually shift towards WES as the first-tier test, microarrays like Reveal SNP Pediatric remain powerful tools in the early stages of the diagnostic journey.
References
- Manning M, Hudgins L. Professional Practice and Guidelines Committee. Array-based technology and recommendations for utilization in medical genetics practice for detection of chromosomal abnormalities. Genet Med. 2010;12(11):742-5. doi: 10.1097/GIM.0b013e3181f8baad.
- Miller DT. Genetic testing for autism: recent advances and clinical implications. Expert Rev Mol Diagn. 2010;10(7):837-40. doi: 10.1586/erm.10.82.
- Shen Y, Dies KA, Holm IA, et al. Autism Consortium Clinical Genetics/DNA Diagnostics Collaboration. Clinical genetic testing for patients with autism spectrum disorders. Pediatrics. 2010 Apr;125(4):e727-35. doi: 10.1542/peds.2009-1684.
- Hodges H, Fealko C, Soares N. Autism spectrum disorder: definition, epidemiology, causes, and clinical evaluation. Transl Pediatr. 2020:S55-S65. doi: 10.21037/tp.2019.09.09.
- Schaefer GB, Mendelsohn NJ. Professional Practice and Guidelines Committee. Clinical genetics evaluation in identifying the etiology of autism spectrum disorders: 2013 guideline revisions. Genet Med. 2013;15(5):399-407. doi: 10.1038/gim.2013.32.
- Huang J, Liu J, Tian R, et al. A Next Generation Sequencing-Based Protocol for Screening of Variants of Concern in Autism Spectrum Disorder. Cells. 2021 Dec 21;11(1):10. doi: 10.3390/cells11010010.
- Du X, Gao X, Liu X, et al. Genetic Diagnostic Evaluation of Trio-Based Whole Exome Sequencing Among Children With Diagnosed or Suspected Autism Spectrum Disorder. Front Genet. 2018 Nov 30;9:594. doi: 10.3389/fgene.2018.00594.