COVID-19 deaths triggered by a gene common in south Asian population, says latest study

Scientists have discovered a gene that doubles the risk of Covid-related respiratory failure and death, which could explain why people of South Asian ancestry are more susceptible to the disease, according to a study published in the journal Nature Genetics.

The gene, which affects how the lungs respond to infection, is the major genetic risk factor discovered so far, and it is carried by around 60% of people of South Asian ancestry compared to 15% of persons of white European descent. The discovery could help to explain why some areas in the United Kingdom are experiencing an increase in fatalities, as well as the impact of COVID-19 on the Indian subcontinent.

Prof James Davies, a geneticist at Oxford University's Radcliffe Department of Medicine and a senior author of the study, told The Guardian that there is a single gene that puts people of South Asian ancestry in danger. Other scientists noted that the findings needed to be confirmed, and that genetic explanations should not be used to dismiss other potentially more serious socioeconomic risk factors that ethnic minorities suffer, such as job exposure and unequal access to healthcare.

The Nature Genetics study on COVID-19 gene

Based on genetic sequencing of tens of thousands of hospital patients in the UK and other countries, the study expands on prior work that discovered a huge chunk of DNA that appears to determine how severely unwell people become from COVID. The most recent research focused on a single gene known as LZTFL1, which was discovered to double the risk of respiratory failure and mortality.

The previously unknown gene was discovered to operate as a switch that activates a critical defence mechanism that inhibits the COVID-19 virus from infected lung epithelial cells. This reaction was suppressed in the high-risk form of the gene, implying that the virus would continue to infiltrate, infect, and damage cells in the lungs for a long time after exposure. Davies noted that the discoveries could lead to new medicines that target the response of lung cells, according to The Guardian report. The majority of current treatments work by altering the immune system's response to the infection.

The findings may provide some insight into why south Asian populations have been the hardest hit by the pandemic. When compared to the general population, the risk of death was three to four times greater for persons of Bangladeshi origin, 2.5 to three times higher for those of Pakistani origin, and 1.5 to two times higher for those of Indian descent in England's second wave. Unlike the excess risk reported in black people in the first wave, once socioeconomic considerations were taken into account, there was still considerable unexplained risk in south Asian groups.

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