Gene variant associated with lung function linked to long COVID risk

A gene variant that increases the risk that a person will develop long COVID has been identified in a large scale genetic study.

People who carry the variant are around 60 percent more likely to develop long COVID following infection by the SARS-Co-V2 virus – which caused the COVID-19 pandemic – according to research published in Nature. The variant is located close to a gene known to play an important role in lung development and respiratory health, which may help explain more about how and why long COVID affects some people and not others.

'Our findings suggest that impaired lung function plays a key role in developing long COVID,' said Dr Hugo Zeberg who co-led the research from the Karolinska Institutet, in Stockholm, Sweden.

The genome-wide association study (GWAS) compared genetic data from 6450 people who had long COVID, with over a million control genomes from unaffected people. The genetic data came from 24 original studies across 16 countries. A second set of genomes from 9500 affected people was used to validate the findings.

The GWAS showed that people with a specific gene variant were around 60 percent more likely to develop long COVID. The variant is located very close to the FOXP4 gene on chromosome 6, which encodes a transcription factor essential for lung development and important in lung regulation and immune responses. Previous studies have shown that FOXP4 is linked to other conditions including lung cancer susceptibility and chronic obstructive pulmonary disease.

The researchers hope their findings will offer an new avenue through which to understand more about long COVID:

'Genetic studies can provide insights into disease risk factors and are particularly powerful for diseases where the exact mechanisms remain unknown,' said co-leader Dr Hanna Ollila from the University of Helsinki in Finland.

'While this gene variant significantly increases risk, it's important to recognise it as just one part of a much larger puzzle,' said Dr Zeberg.