, Volume 19, Issue 2, pp 105–110 | Cite as

Genetic test utilization and diagnostic yield in adult patients with neurological disorders

  • Tanya M. Bardakjian
  • Ingo Helbig
  • Colin Quinn
  • Lauren B. Elman
  • Leo F. McCluskey
  • Steven S. Scherer
  • Pedro Gonzalez-AlegreEmail author
Original Article


To determine the diagnostic yield of different genetic test modalities in adult patients with neurological disorders, we evaluated all adult patients seen for genetic diagnostic evaluation in the outpatient neurology practice at the University of Pennsylvania between January 2016 and April 2017 as part of the newly created Penn Neurogenetics Program. Subjects were identified through our electronic medical system as those evaluated by the Program’s single clinical genetic counselor in that period. A total of 377 patients were evaluated by the Penn Neurogenetics Program in different settings and genetic testing recommended. Of those, 182 (48%) were seen in subspecialty clinic setting and 195 (52%) in a General Neurogenetics Clinic. Genetic testing was completed in over 80% of patients in whom it was recommended. The diagnostic yield was 32% across disease groups. Stratified by testing modality, the yield was highest with directed testing (50%) and array comparative genomic hybridization (45%), followed by gene panels and exome testing (25% each). In conclusion, genetic testing can be successfully requested in clinic in a large majority of adult patients. Age is not a limiting factor for a genetic diagnostic evaluation and the yield of clinical testing across phenotypes (almost 30%) is consistent with previous phenotype-focused or research-based studies. These results should inform the development of specific guidelines for clinical testing and serve as evidence to improve reimbursement by insurance payers.


Diagnostic yield Next-generation sequencing Whole exome sequencing Neurology 


Funding information

This study was supported by the Neurogenetics Translational Center of Excellence, Department of Neurology, University of Pennsylvania.

Compliance with ethical standards

This study was approved by the Institutional Review Committee at the University of Pennsylvania. As an IRB-approved retrospective analysis, approval to conduct this study by an ethical standards committee was received.

Supplementary material

10048_2018_544_MOESM1_ESM.xlsx (22 kb)
Supplementary Table 1 Variants of unknown significance. The tab named “VUS” indicates those variants still unresolved at the end of the study. The Tab named “Resolution Pathogenic” indicates VUS reclassified as pathogenic. MAF: minor allele frequency in ExAC. Note that the number of VUS remaining is higher than the final number of patients with VUS, as subjects can have multiple VUS. (XLSX 21 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Tanya M. Bardakjian
    • 1
  • Ingo Helbig
    • 1
    • 2
  • Colin Quinn
    • 1
  • Lauren B. Elman
    • 1
  • Leo F. McCluskey
    • 1
  • Steven S. Scherer
    • 1
  • Pedro Gonzalez-Alegre
    • 1
    • 2
    Email author
  1. 1.Department of NeurologyUniversity of PennsylvaniaPhiladelphiaUSA
  2. 2.The Children’s Hospital of PhiladelphiaPhiladelphiaUSA

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