Fig. 2.
Alteration of oral microbiota in patients with AD. A) Stacked bar plots of average relative abundance at the phylum and family taxonomic levels. Top 6 phyla (representing 99.3% of all sequence reads) and top 14 families (representing 87% of all sequence reads) are shown. B) Alpha diversity measurements for patients with AD and MCI and at-risk group versus healthy controls (Chao1 AD = 174, Chao1 control = 144, Chao1 MCI = 144, Chao1 at-risk = 195; Shannon AD = 3.9, Shannon control = 3.7, Shannon MCI = 3.6, Shannon at-risk = 4.1). C) NMDS plot of Bray–Curtis dissimilarities (NMDS, stress value = 0.22) displays sample-wise differences in community composition between health conditions (coloration with respect to group membership, group centroids indicated by large symbols). Marginal boxplots display the grouped distribution of individuals/samples along the respective dimensions of the NMDS plot. (D) Differential abundance analysis identified 32 ASVs that were increased and 7 ASVs that were decreased in AD relative to control participants (PFDR < 0.05) as well as 2 ASVs increased and 1 ASV decreased in patients with MCI relative to control participants. Each point represents an ASV. ASVs to the right of the zero line are more abundant and ASVs to the left of the zero line are less abundant in AD and MCI compared with control groups. MCI, mild cognitive impairment; AD, Alzheimer's disease.