South Asian populations have higher genetic susceptibility to COVID-19 . . .
A study recently published by researchers at the University of Oxford describes the identification of a gene, LZTFL1, which is linked to a doubling of the risk of respiratory failure due to COVID-19. The high-risk version of this gene increases the risk of developing severe COVID-19 by preventing the cells lining the lungs from adequately mounting a protective response to the virus. The study also notes that the high-risk version of this gene is present in up to 60 per cent of individuals of South Asian ancestry, compared with only 15 per cent of individuals of European ancestry.
Gene may have contributed to increased mortality in U.K., India . . .
This heightened genetic risk may have been a factor in the increased rates of COVID-related mortality experienced by India and by the South Asian population in the U.K., where rates of mortality were between 1.5 and four times higher for people of Bangladeshi, Pakistani, and Indian ethnicity, even after correction for socioeconomic factors. In India, where the official death toll sits at 465,911, the actual toll based on excess mortality (a measure of all-cause mortality in excess of historical trends that captures deaths attributable to COVID even if they were never tested) has been estimated to be between 3.4 and 4.9 million. Despite a lack of data dis-aggregated by ethnicity early in the pandemic, there have also been indications that South Asian communities in Canada have been disproportionately affected, including in the Fraser Health Authority of British Columbia. Although socioeconomic and cultural factors such as high-risk occupations and large households almost certainly play a role as drivers of transmission, the discovery of the LZTFL1 gene implicates genetics as an additional potential vulnerability facing this population.
Discovery has implications for pandemic response, future research . . .
Identifying the excess mortality risk posed by the LZTFL1 gene may assist in the pandemic response by identifying populations and communities that would most benefit from public health and vaccination campaigns. The mechanism by which the high-risk version of LZTFL1 results in increased mortality does not involve the immune system. This means that individuals with this version of the gene can still mount a normal immune response to vaccination; thus, vaccination is even more beneficial to this population. As well, the development of novel therapeutics that specifically target the lungs may also be a promising avenue of future research.