How come, after RNA isolation, PCR shows two bands (18S 28S) but these bands dont show after DNase I treat?

RNA is pretty delicate stuff- most likely your kit is degrading it. I was using a kit that involved heating the RNA following DNase treatment to 70 degrees and this completely degraded the RNA as seen on the agilent bioanalyser. My advice would be to test the quality using the agilent/experion bioanalyser for 18 and 28s. Also look for RNA isolation kits or individual DNase kits that involve eluting off columns/ gel matrix and these work fine for me!How come, after RNA isolation, PCR shows two bands (18S 28S) but these bands dont show after DNase I treat?
May be it got chewed up into tiny pieces and ran off your gel.How come, after RNA isolation, PCR shows two bands (18S 28S) but these bands dont show after DNase I treat?
are you using a kit? a similar thing happened to us, and we just switched companies and the samples worked fine
It has been my experience that some DNAse I preparations are contaminated with RNAse! Try to obtain some RNAse free DNAse and try again.





Good luck.
Your question is nonsense. Please give more details. Like did you do a reverse transcription reaction on the RNA first. What primer set did you use for the PCR etc.





If you got a PCR product before DNAse treatment, but not afterwards then your RNA was contaminated with DNA and your PCR was probably just amplifying genomic DNA. Anyway please clarify what you did.