Real-Time PCR assay was used to detect sensitivity of target genes in relevant body fluids or tissues (For blood samples, n = 10; for saliva, oral mucosa and nasal secretion, n = 8; for menstrual blood samples, n = 5; for vaginal secretion samples, n = 5; for urine samples, n = 16) (a). Expression levels of target markers in each body fluid were compared with dCt values, calculated by subtracting the Ct value of 18S-rRNA (internal standard) from that of the target gene. Smaller dCt value indicates higher expression of the target gene. A dCt value of 25 indicates the cut-off value of target gene expression. Comparisons of HTN3, STATH and KRT4 mRNA levels among body fluids (b∼d). Each experiment was repeated twice. Bars represent means ± standard deviations (SD) and averages were compared using a two tailed Student's t-test assuming unequal variances with a 5% significance level (*, P≤0.05; **, P≤0.01; ***, P≤0.001).