Diagnostic yield of panel-based genetic testing in syndromic inherited retinal disease

Eur J Hum Genet. 2020 May;28(5):576-586. doi: 10.1038/s41431-019-0548-5. Epub 2019 Dec 13.

Abstract

Thirty percent of all inherited retinal disease (IRD) is accounted for by conditions with extra-ocular features. This study aimed to establish the genetic diagnostic pick-up rate for IRD patients with one or more extra-ocular features undergoing panel-based screening in a clinical setting. One hundred and six participants, tested on a gene panel which contained both isolated and syndromic IRD genes, were retrospectively ascertained from the Manchester Genomic Diagnostics Laboratory database spanning 6 years (2012-2017). Phenotypic features were extracted from the clinical notes and classified according to Human Phenotype Ontology; all identified genetic variants were interpreted in accordance to the American College of Medical Genetics and Genomics guidelines. Overall, 49% (n = 52) of patients received a probable genetic diagnosis. A further 6% (n = 6) had a single disease-associated variant in an autosomal recessive disease-relevant gene. Fifty-two percent (n = 55) of patients had a clinical diagnosis at the time of testing. Of these, 71% (n = 39) received a probable genetic diagnosis. By contrast, for those without a provisional clinical diagnosis (n = 51), only 25% (n = 13) received a probable genetic diagnosis. The clinical diagnosis of Usher (n = 33) and Bardet-Biedl syndrome (n = 10) was confirmed in 67% (n = 22) and 80% (n = 8), respectively. The testing diagnostic rate in patients with clinically diagnosed multisystemic IRD conditions was significantly higher than those without one (71% versus 25%; p value < 0.001). The lower pick-up rate in patients without a clinical diagnosis suggests that panel-based approaches are unlikely to be the most effective means of achieving a molecular diagnosis for this group. Here, we suggest that genome-wide approaches (whole exome or genome) are more appropriate.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Child
  • Child, Preschool
  • Eye Diseases, Hereditary / diagnosis
  • Eye Diseases, Hereditary / genetics*
  • Female
  • Genetic Testing / methods
  • Genetic Testing / standards*
  • High-Throughput Nucleotide Sequencing / methods
  • High-Throughput Nucleotide Sequencing / standards*
  • Humans
  • Infant
  • Male
  • Middle Aged
  • Phenotype
  • Retinal Diseases / diagnosis
  • Retinal Diseases / genetics*
  • Sensitivity and Specificity
  • Sequence Analysis, DNA / methods
  • Sequence Analysis, DNA / standards*
  • Syndrome