Mapping the subgingival HerBiome and HisBiome over the human healthspan

Periodontal (gum) diseases are caused by a breakdown in the intricate balance between bacteria that live under the gumline and the local immune response. Since periodontal diseases have been reported to be more common in men than in women, we set out to investigate whether these bacterial communities are intrinsically different between the 2 sexes, and whether these differences are sustained over the lifespan. Using deep-sequencing technology to analyze the microbiomes of 941 individuals, we discovered that sex at birth is indeed a determining factor in the types of bacteria that live under the gums. Aging trajectories and patterns also differ between men and women, with women demonstrating a distinct shift after 30 years of age, and men showing no definite age-based change. These findings have important implications for the cause of periodontitis in either sex, as well as the potential to personalize therapy based on age and sex.