Whole exome sequencing (WES) is a powerful test for individuals suspected of having an underlying genetic diagnosis. However, WES increases the likelihood of unexpected findings, which may or may not be clinically significant. Further, due to methodological limitations, WES may not always be the correct test to order as WES will not detect all genetic causes of disease (for example, it will not detect chromosomal structural differences). Both informative and uninformative results can lead to complex patient and family psychosocial repercussions, and could impair future insurability. Genetic counselling facilitates informed decision-making. Given complexity of results, WES should only be ordered after counselling by a qualified health care provider.

Conditions: Whole exome sequencing (WES)

Treatments: Genetic counselling

Sources

• Boycott K, et al. The clinical application of genome-wide sequencing for monogenic diseases in Canada: Position Statement of the Canadian College of Medical Geneticists. J Med Genet. 2015 Jul;52(7):431-7. (PubMed)
• Krabbenborg L, et al. Understanding the Psychosocial Effects of WES Test Results on Parents of Children with Rare Diseases. J Genet Couns. 2016 Dec;25(6):1207-1214. (PubMed)
• Sawyer SL, et al. Utility of whole-exome sequencing for those near the end of the diagnostic odyssey: time to address gaps in care. Clin Genet. 2016 Mar;89(3):275-84. (PubMed)