Scientists are exploring whether the rise of modern autoimmune diseases is linked to ancient genetic adaptations that once helped humans survive deadly historical threats.
According to research highlighted in The New York Times, conditions such as multiple sclerosis, rheumatoid arthritis, Type 1 diabetes, lupus, and Crohn's disease affect millions of people, particularly in industrialized countries where rates are climbing. These illnesses occur when the immune system mistakenly attacks healthy tissues and organs instead of focusing on outside invaders like bacteria and viruses.
Researchers suggest that the origins of these vulnerabilities may lie in antagonistic pleiotropy—a biological phenomenon where specific gene variants help humans in one environment but harm them in another. Studies analyzing ancient human DNA indicate that certain immune-related gene variants spread rapidly during major historical shifts, such as the Bronze Age migration of pastoralists roughly 5,000 years ago and the 14th-century Black Death pandemic.
During those eras, these genetic adaptations provided a vital survival advantage against infectious diseases, zoonotic pathogens, and mass mortality events. However, in the modern era of advanced sanitation, antibiotics, and improved hygiene, those same hyper-sensitive immune responses can become risk factors for chronic autoimmune disorders.
