57: Low rates of genetic testing in Medicaid-enrolled children with ASD and ID

Brown TR et al., Genetics in Medicine - This episode reviews a claims-based study of 241,060 Medicaid-enrolled children (ages 7–17) from 2008–2016 that measured use of genetic testing among those with ASD-only, ID-only, and ASD+ID. The authors report low overall testing rates, temporal shifts in test modalities from cytogenetics/Fragile X toward chromosomal microarray and gene panels, and disparities by race and urbanicity. We outline the methods, key findings, and clinical implications for guideline implementation and access to genetic services. Key terms: autism spectrum disorder, intellectual disability, genetic testing, Medicaid, chromosomal microarray. Study Highlights:Using T-MSIS Medicaid claims data from 2008–2016, the authors identified 241,060 children with ASD-only, ID-only, or ASD+ID and measured cumulative genetic testing via CPT codes. Genetic testing frequencies were low: ASD+ID 25.94%, ASD-only 16.86%, ID-only 13.09%, versus 1.23% in a random sample without these diagnoses. Testing modalities were dominated by cytogenetics and Fragile X through 2013, with increasing use of chromosomal microarray and gene panels in 2014–2016. The study also found lower adjusted odds of testing for Black children and for those in suburban or rural areas. Conclusion:Clinical implementation of guideline-recommended genetic testing among Medicaid-enrolled children with neurodevelopmental disorders was low from 2008–2016, indicating missed opportunities and the need to identify barriers to testing. Music:Enjoy the music based on this article at the end of the episode. Article title:Medicaid claims from 2008 to 2016 indicate low rates of genetic testing among children with intellectualdisability and autism spectrum disorder First author:Brown TR Journal:Genetics in Medicine DOI:10.1016/j.gim.2025.101451 Reference:Brown TR, Lee W-L, Ventimiglia J, et al. Genetics in Medicine (2025). doi: https://doi.org/10.1016/j.gim.2025.101451 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/genetic-testing-medicaid-asd-id-low-rates QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2025-06-27. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript portions describing (1) study design and cohort, (2) testing frequencies by diagnosis, (3) modality timeline, (4) disparities by race/urbanicity/sex, (5) age at first testing, and (6) barriers and implications discussed in the conclusion.- transcript topics: Medicaid cohort construction and eligibility (2008-2016, 241,060 children, no private insurance); Genetic testing frequencies by diagnosis (ASD-only, ID-only, ASD+ID, random); Testing modality timeline (cytogenetics/Fragile X pre-2013; CMA and gene panels 2014-2016); Odds ratios and demographic disparities (race, urbanicity, sex); Age at first genetic testing; Clinical inertia and administrative barriers to testing QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 5- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factua...