As the use of large panels, whole exome and whole genome sequencing increases, so arises the potential to uncover clinically relevant genetic variants unrelated to the genetic test request – variously termed “incidental”, “secondary” or “additional” findings. The American College of Human Genetics (ACMG) recommends the return of likely pathogenic/pathogenic variants in 59 medically actionable genes, irrespective of indication for testing.
In 2017, we conducted a survey of Australian clinically accredited genetic testing laboratories to evaluate practices around annotation, storage, curation and reporting of such findings. Laboratories were re-surveyed in April 2020 to seek updated opinions. Responses were collated for 20 laboratories performing single variant to whole genome sequencing. After exclusion of three laboratories conducting limited testing (IVF, single variant), results were analyzed for 17 laboratories.
Findings include:
- Consistent with results of the previous survey, there is no Australian consensus on a term to describe these findings. Further, 8/17 (47%) laboratories indicated that they use multiple terms: 2/8 (25%) alternated depending on the context of the finding, and 3/8 (38%) used two or more terms interchangeably.
- Services performing panel testing were more likely to indicate that they would report-back findings outside of the indication for testing in relation to carrier status, pharmacogenetic markers, and adult-onset disorders in adult and pediatric cases.
- 13/17 (76%) laboratories are notified via the consent/test request form about whether a patient has consented to return of these findings.
- 15/17 (88%) laboratories store findings in laboratory databases, even if not reported.
- All 9 WES/WGS services do not routinely analyze a list of medically actionable genes outside of the patient’s indication for testing (e.g. ACMG 59).
Thematic analysis of written policies from seven laboratories indicated little consistency in their content and format. These findings provide rationale to explore development of consistent policies around report-back of incidental/secondary/additional findings in Australia.