Definitions

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  Primary indication: The constellation of clinical features that lead to diagnostic evaluation by genome-wide sequencing.
  
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  Medically actionable: A finding that may impact patient management to improve outcome.
  
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  Genetic heterogeneity: The occurrence of similar or identical phenotypes as a result of disruption of different genes.
  
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  Monogenic (Mendelian) condition: A genetic condition resulting from altered function of a single gene/locus.
  
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  Multifactorial inheritance: Non-monogenic inheritance of specific traits that are determined by the combined action of multiple genetic and environmental factors.
  
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  NGS: Massively parallel sequencing technologies that produce many hundreds of thousands or millions of reads simultaneously.
  
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  Multigene panel sequencing: For the purpose of this document, multigene panel sequencing will refer to the targeted sequencing, primarily by NGS, of a selection of genes associated with a specific clinical presentation. Genes included in panels typically have a depth of coverage sufficient to minimise false negatives.
  
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  Whole-genome sequencing (WGS): A process used to determine the sequence of most of the DNA content encompassing the entire genome of an individual.
  
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  Whole-exome sequencing (WES): A process used to determine the DNA sequence of most of the protein-encoding exons found in the genome of an individual.
  
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  Clinical genome-wide sequencing: A generic term for the process used to determine the sequence of most, if not all, clinically significant genes and its associated interpretation, including bioinformatic analysis and clinical genotype–phenotype correlation. This approach would be undertaken by an appropriately certified laboratory to address a clinical question.
  
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  Primary finding: Genetic variant(s) identified by genome-wide sequencing that explain the primary indication for testing.
  
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  Incidental finding: Genetic variant(s) identified by genome-wide sequencing unrelated to the primary indication for testing.