A key gene that doubles the risk of death from Covid-19 has been discovered by scientists.
The gene, known as LZTFL1, prevents the cells lining airways and the lungs from protecting themselves against the attacking virus.
The discovery by Oxford University scientists partially explains why more people with ancestry from the Indian subcontinent have been killed by the virus.
The risky form of the LZTFL1 gene is found in 60% of people with South Asian compared to 15% of those with European ancestry.
It means people could be tested for the gene and drugs boosting the cells in the respiratory tract developed.
The lead scientist on the study which made the discovery Prof James Davies worked as an NHS consultant in intensive care during the pandemic.
Prof Davies, of Oxford University, said: “The genetic factor we have found explains why some people get very seriously ill after coronavirus -1>coronavirus infection.
“It shows that the way in which the lung responds to the infection is critical. This is important because most treatments have focussed on changing the way in which the immune system reacts to the virus.”
The findings, published in Nature Genetics, could also go some way to explain the devastating impact of Covid-19 in India.
Dr Raghib Ali, of Cambridge University, who is a Government adviser on Covid-19 and ethnicity, said: “This is an important study.
“Although the higher death rate we have seen in ethnic minorities is primarily due to their higher risk of infection, which is driven by their higher likelihood of living in densely-populated urban areas, in larger and multi-generational households and to work in public-facing roles, there has been an unexplained residual excess risk in South Asians even after taking these risk factors into account.
“Other studies from Public Health England, ISARIC and ICNARC have also shown that South Asians, and Bangladeshis in particular, – but not black groups – have worse survival than whites.
“This study shows that this may be due to them being more likely to carry this gene which increases their risk of death once infected.”
The research team trained an artificial intelligence algorithm to analyse vast amounts of genetic data from hundreds of types of cells from all parts of the body.
Dr Damien Downes, who led the laboratory work, said: “Surprisingly, as several other genes were suspected, the data showed that a relatively unstudied gene called LZTFL1 causes the effect.”
Prof Davies added: “Although we cannot change our genetics, our results show that the people with the higher risk gene are likely to particularly benefit from vaccination.
“Since the genetic signal affects the lung rather than the immune system it means that the increased risk should be cancelled out by the vaccine.”
