Figure 2: Neighbor-joining tree based on the SSU-rRNA region sequences showing the phylogenetic relationship between Blastocystis isolates. The bootstrap values were computed over 1 000 replicates. Acute urticaria, chronic urticaria, and control isolates are indicated by “AU”, “CU”, and “C”, respectively. The sequences of strains isolated from the patients with acute urticaria, those with chronic urticaria and the control group are represented by a black triangle, black square, and black circle, respectively. The white squares represent the reference sequences from each subtype. Proteromonas lacerate (AY224080) was used as an out-group during phylogenetic analysis. Scale bar: 0.02 nucleotide substitutions per alignment position.