Genetic Testing of Neurodevelopmental Disorders in Israel.

This study looked at genetic testing for autism and other developmental conditions in over 25,000 Israeli children. Only about 1 in 4 eligible children actually received genetic testing, even though it's recommended as standard care. Children from minority backgrounds and lower-income families were much less likely to be diagnosed with autism in the first place, meaning they missed out on genetic counseling and testing. The research shows major gaps in accessing genetic services that could help families understand their child's condition.

This large population-based study in Israel examined genetic testing patterns among 25,403 children with neurodevelopmental disorders born 2000-2020. Despite chromosomal microarray analysis being the first-line genetic test for autism and intellectual disability, only 38.7% of eligible children received genetic counseling and 24.5% underwent testing. Testing rates were higher for children with multiple conditions (36.9%) versus autism alone (21.2%). Significant disparities existed, with autism diagnosis rates 54-83% lower in minority and lower socioeconomic populations, limiting access to genetic services.

Over one-third of counseled families did not proceed to testing, highlighting barriers beyond initial counseling access.

Results highlight need for systematic approaches to improve genetic testing access and autism recognition across all populations. Healthcare systems should examine barriers preventing families from proceeding to testing after counseling. Targeted interventions needed to address diagnostic disparities in minority and lower socioeconomic communities to ensure equitable access to genetic services.

Study limited to one Israeli health system, potentially limiting generalizability. Abstract does not specify reasons for non-uptake of testing after counseling. Sociodemographic factors affecting diagnostic disparities not fully detailed. Follow-up periods varied by birth year, potentially affecting testing rate comparisons.

Genetic testing is the criterion standard for diagnosing neurodevelopmental disorders (NDDs), with chromosomal microarray analysis (CMA) used as a first-line test for autism, intellectual disability, or global developmental delay. Despite advancements in genetic testing technologies and integration into health care systems, data on clinical use remain limited. To evaluate genetic counseling and testing rates in patients with major NDDs and these individuals' clinical and sociodemographic characteristics. This longitudinal, retrospective, population-based cohort study analyzed electronic health records of individuals born between 2000 and 2020 and insured by Clalit Health Services, the largest health maintenance organization in Israel.

Follow-up extended through December 6, 2023. Patients diagnosed with autism spectrum disorder, intellectual disability or global developmental delay, epilepsy, or cerebral palsy (major NDDs) were included. Neurodevelopmental disorders. The outcome was the rate of genetic counseling, CMA testing, and NDD diagnosis measured using descriptive statistics.

Of 2 406 763 individuals born in Israel between 2000 and 2020, 25 403 (1.06%; mean [SD] age at December 6, 2023, 11.9 [4.3] years; 68.7% male) were diagnosed with a major NDD. The cohort was predominantly of middle socioeconomic status (56.5%), and autism was the most common diagnosis (40.6%). Among 18 709 children indicated for CMA (ie, those with autism, intellectual disability or global developmental delay, or multiple diagnoses), 7233 (38.7%) received genetic counseling, and 4592 (24.5%) underwent testing (63.5% of those counseled). Genetic testing rates were higher in children with multiple co-occurring NDDs (1478 of 4005 [36.9%]) compared with those with autism alone (2189 of 10 311 [21.2%]).

Genetic counseling rates were lowest for cerebral palsy and epilepsy as guidelines were less established. Genetic evaluation rates increased with more recent birth cohorts. While evaluation rates were similar across subpopulations for children with a diagnosis, initial autism diagnosis rates were 54% to 83% lower in lower socioeconomic status and minority populations, limiting access to counseling and testing. A key finding of this cohort study was that more than one-third of patients who received genetic counseling did not undergo testing.

Furthermore, low socioeconomic status and minority populations experienced drastic underdiagnosis of autism. These findings underscore the need for national initiatives to improve awareness and access to counseling and testing for all major NDDs and the recognition of autism in minority groups.