Narrator: This is Science Today. Since the beginning of
industrialization, allergic and autoimmune diseases have been on the rise. Many
scientists believe an explanation for this is the "Hygiene Hypothesis," which
proposes that a lack of early exposure to pathogens increases the risk of
developing allergic and autoimmune disorders later in life. Researchers at the
University of California, Berkeley recently discovered that pathogens were the
single most influential environmental factor on shaping genetic diversity in
believe that this is evidence supporting the so-called hygiene hypothesis.
Narrator: Study leader Matteo Fumagalli and his team also discovered that
many of the genes shaped by pathogen interaction were also associated with autoimmune
immune system has been shaped by an environment full of pathogens. So, now we
live in a different environment with less pathogens. So this could be one of
the causes of autoimmune disease.
Narrator: For Science Today, I'm Larissa Branin.