The Black Death epidemic was one of the most striking pandemics in human history. According to studies, in addition to mortality rates (about 50% of the total population died from the disease), bubonic plague also altered human DNA.
This is according to a study published in the magazine nature last Wednesday (19). Developed by anthropologists and geneticists from McMaster University and the University of Chicago, the research has identified that the frequency of genes that shape our immune system has been altered. Whether or not this is good for modern humans is unknown.
To reach this conclusion, the team of scientists studied the genetic data of more than 200 people who died before the Black Death, during the deadly pandemic, and then in London and Denmark.
The research suggests the pandemic was a selective evolutionary pressure on humans and altered the diversity of genetic variants of at least four immune system genes.
Other later experiments with immune cells suggested that variants of the four genes protected our bodies against the bacterium that causes bubonic plague, as well as other pathogens. The authors also note, however, that some of the genes were associated with an increased risk of autoimmune diseases such as Crohn’s disease, rheumatoid arthritis and lupus.