The Genetic Connection between COVID-19 and Lupus

May 16, 2023

Studies on COVID-19 reveal that genetic differences between people impact the severity of the disease. Those genetic differences affect the immune response pathways, including those that play a part in autoimmune diseases. 

That prompted scientists to compare the genetics of severe COVID-19 and autoimmune diseases such as systemic lupus erythematosus (lupus). They embarked on the question of which genetic loci (a fragment of a person’s DNA) impact both diseases and which biological processes are involved. 

The research revealed several genetic loci that impacted the severity of COVID-19 were also involved in lupus. In those loci, researchers identified alleles, that is, versions of the genes, that influenced the severity of COVID-19 and Lupus. 

Research revealed that the locus that shows the most association between COVID-19 and Lupus contains the gene TYK2, which codes for a protein involved in interferon production. Interferon production plays an important role in response to viral infection. It is known that this process is dysregulated in Lupus patients. 

The TYK2 had opposing effects on COVID-19 severity and Lupus susceptibility, which is in line with the hypothesis stating that some alleles that persist in the human population represent a risk for Lupus, but at the same time, they have a protective effect against pathogens (including viruses).

Researchers also identified locus presenting a risk for Lupus and severe COVID-19. This shared locus contains a gene called CLEC1A; it codes for a protein known as a lectin that plays a role in signaling between cells. Researchers hypothesized that despite being a risk for Lupus and COVID-19, it still exists in the population because it plays a protective role in fungal infections.

Results presented in this study are an additional piece of evidence pointing to the existence of alleles in human DNA that protect against viral infection and can affect a person’s susceptibility to autoimmune diseases.