Figure 1. Non-metric multidimensional scaling (NMDS) of t-RFLP peak areas.

Subgingival plaque is shown in Figure 1A, saliva in 1B, and supragingival plaque in 1C. Non-Hispanic blacks are indicated by red, non-Hispanic whites are in green, Chinese are in blue, and Latinos are indicated by orange. Significant ethnicity-based clustering was seen in subgingival and saliva samples (Subgingival stress value = 0.09, Saliva stress value = 0.11, Supragingival stress value = 0.12).