Five of the 14 urine samples were associated with symptoms and there were no significant differences in the abundance of any of these genes between the symptomatic E. coli UTI and asymptomatic E. coli bacteriuria (P > 0.05, Wilcoxon rank sum test), but there was a trend towards a higher abundance of CsgBAC and BarA in the symptomatic E. coli UTI than the asymptomatic E. coli bacteriuria (P = 0.08, P = 0.08, Wilcoxon rank sum test, respectively) (Supplementary Fig. 4a–e). This evidence concerns the gene LIN9 and bacterial urinary tract infection.