The stability of RNA extracted from the whole saliva stored at room temperature. Saliva was collected respectively from two healthy individuals and stored in the Saliva RNA tubes for up to four weeks. Total RNA was extracted at different time intervals. The transcripts of β-actin were detected using the qRT-PCR assay at different weeks. (A) The Cq values of the the two samples at different weeks. The Cq for the male and female saliva were calculated to be 26.00 × 0.70 and 25.34 × 0.43, respectively. (B) The ΔCq values of the two samples at different weeks. ΔCq = CqRT(−) - CqRT(+), where CqRT(+) was the Cq values obtained from the extracted RNA with reverse transcription, whereas CqRT(-) was the Cq values obtained without reverse transcription.