What Is The S-gene Drop Out?
The Omicron variant of the SARS-CoV-2 virus has been confirmed in India and in at least 30 other countries by the World Health Organization (WHO).
- While the variant can only be reliably confirmed with genome sequencing, the WHO has also recommended that certain commonly used COVID-19 detection tests, with ‘S-gene dropout’ capabilities, can be used to quickly screen for an Omicron infection.
- Tests usually look for three target genes related to parts of the virus: S (spike), N2 (nucleocapsid or inner area) and E (envelope or outer shell).
- The S-gene refers to the gene that codes for the spike protein, or the most distinctive part of the coronavirus.
- The SARS-CoV-2, like many other coronaviruses, has key protein-regions that define its structure: The envelope protein (E), thenucleocapsid protein(N), the membrane protein (M) and the spike protein (S).
- To accurately identify the virus, diagnostic tests are made that can identify characteristic genes that make these proteins.
