Genes that helped people survive the infamous medieval plague epidemic known as the Black Death seem to be helping humans fight against infections today, according to a new study published this week.
The research, led by scientists from the University of Bristol in collaboration with their colleagues from several other British universities such as Imperial College London, focused on particular variants, or alleles, of the ERAP2 gene.
Previous studies revealed that people who possessed these alleles had better odds of surviving the aforementioned plague pandemic as compared to those who did not have them, a press release by the University of Bristol noted.
The new study suggests that these same alleles continue to afford humans protection against bubonic plague and other infections, such as COVID-19.
“This gene essentially chops up proteins for the immune system," said Dr. Fergus Hamilton, lead author of the study.
He did point out, however, that there appears to be a tradeoff of sorts, and that these genes apparently make people more susceptible to other diseases.
"Although we don't know the exact mechanism influencing disease risk, carriers of alleles that provide more protection against respiratory disease seem to have an increased risk of autoimmune disease,” Hamilton mused. “It is potentially a great example of a phenomenon termed 'balancing selection' - where the same allele has a different effect on different diseases."