On Jun. 29, 2020, National Institutes of Health (NIH) researchers announced they had discovered that Mediterranean populations may be more susceptible to an autoinflammatory disease because of evolutionary pressure to survive the bubonic plague.

The study, carried out by scientists at the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health, determined that specific genomic variants that cause a disease called familial Mediterranean fever (FMF) may also confer increased resilience to the plague.

The researchers suggest that because of this potential advantage, FMF-causing genomic variants have been positively selected for in Mediterranean populations over centuries. The findings were published in the journal Nature Immunology. Additional support for the research was provided by the National Institute of Allergy and Infectious Diseases, the National Institute of Arthritis and Musculoskeletal and Skin Diseases and the Center for Research on Genomics and Global Health.

Over centuries, a biological arms race has been fought between humans and microbial pathogens. This evolutionary battle is between the human immune system and microorganisms trying to invade our bodies. Microbes affect the human genome in many ways. For example, they can influence some of the genomic variation that accumulates in human populations over time. 

These findings, in combination, indicate that over centuries, FMF-causing genomic variants positively selected in Turkish populations play a role in providing resistance to Yersinia pestis infection. Whether the same is true for other Mediterranean populations remains to be seen. The study offers a glimpse into the unexpected and long-lasting influence of microbes on human biology.