 ##  [Keystone-Pathogen Hypothesis](/keystone-pathogen-hypothesis) 

  ##  [Keystone-Pathogen Hypothesis](https://health.quantumdictionary.io/keystone-pathogen-hypothesis-0) 

  
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**Health &amp; Life Sciences Dictionary**

 
Definition

A hypothesis that certain microbial species, although present at low abundance within the oral microbiome, exert disproportionate influence on community composition, immune modulation or ecological interactions such that their presence precipitates dysbiosis and disease.