Abstract:
Next-generation sequencing (NGS) has truly transformed
human genetics and is now an integral discovery
tool in the field. Whole-exome sequencing
(WES) – an NGS application focused on the proteincoding
regions of the human genome – has already
bridged the bench-to-bedside divide internationally and is offered as
a clinical test by several accredited laboratories. Clinical WES is not
currently offered in South Africa (SA) for a number of reasons, including
technological constraints, insufficient storage for the resulting large
datasets, ethical considerations and limitations of our understanding
of the impact of human genetic variants on health and in terms of
clinical utility. The historical under-representation of individuals of
black African descent in genomics research further complicates the
interpretation of results obtained from WES data in black Africans.
Concurrently, the application of WES for preventive healthcare
in seemingly healthy individuals is progressing rapidly. WES offered
as a direct-to-consumer (DTC) genetic test to healthy individuals in
aid of wellness and future disease risk prediction raises many critical
considerations, some of which were highlighted previously in the SAMJ by
the Southern African Society for Human Genetics. This topic is currently
back in the headlines as local health insurance company Discovery Health
launched their suite of personalised medicine products, which includes
WES.[5-7] This offering is presented in partnership with US-based company
Human Longevity, Inc. (HLI) under the leadership of J Craig Venter.
